Ardour 6.6 crashes when adding track with LinuxSampler LV2

Hi all, I’m still somewhat of a Linux and Ardour novice so please excuse me if this isn’t the correct place to ask.

I am running AV Linux MX Edition, and I had this same problem with the pre-installed 6.5 version of Ardour when trying to use LinuxSampler as an LV2 plugin. Therefore, in order to check it first with v6.6 before enquiring here, I have subscribed, downloaded and installed it but it behaves just the same: I find myself back on the desktop with Ardour no longer running.

I’m using v2.1.1 of the LinuxSampler LV2 plugin which I downloaded and installed from the KXStudio repositories using the Synaptic Package Manager included with AVL-MXE.

I can also report that the LinuxSampler LV2 plugin runs without crashing REAPER (v6.24 and v6.26) which is also installed on the same system.

Here is my Ardour Log.

2021-04-15T14:08:10 [INFO]: AlsaAudioBackend: adjusted output channel count to match device.
2021-04-15T14:08:10 [INFO]: AlsaAudioBackend: adjusted input channel count to match device.
2021-04-15T14:08:10 [WARNING]: LADSPA: cannot load module "/usr/lib/ladspa/ladspa_guitarix.so" (/usr/lib/ladspa/ladspa_guitarix.so: undefined symbol: _ZN4Glib10Dispatcher7connectEON4sigc4slotIvNS1_3nilES3_S3_S3_S3_S3_S3_EE)
2021-04-15T14:08:20 [WARNING]: Unsupported required LV2 feature: 'http://lv2plug.in/ns/ext/buf-size#fixedBlockLength' in 'Vex'.
2021-04-15T14:08:22 [INFO]: harvid version: 803
2021-04-15T14:08:24 [INFO]: Loading menus from /opt/Ardour-6.6.0/etc/ardour.menus
2021-04-15T14:08:25 [INFO]: Loaded custom session defaults.
2021-04-15T14:08:25 [INFO]: Loading user ui scripts file /home/Me/.config/ardour6/ui_scripts
2021-04-15T14:08:25 [INFO]: Loading plugin order file /home/Me/.config/ardour6/plugin_metadata/plugin_order
2021-04-15T14:08:25 [INFO]: Loading history from /media/Me/DATA/Ardour Projects/Untitled-2021-04-15-14-07-51/Untitled-2021-04-15-14-07-51.history
2021-04-15T14:08:25 [INFO]: Untitled-2021-04-15-14-07-51: no history file "/media/Me/DATA/Ardour Projects/Untitled-2021-04-15-14-07-51/Untitled-2021-04-15-14-07-51.history" for this session.

And here is the Log right up to the crash after running Ardour from the Terminal.

    ___   ___       __  ____  _____ 
   /_\ \ / / |  ___|  \/  \ \/ / __|
  / _ \ V /| |_|___| |\/| |>  <| _| 
 /_/ \_\_/ |____|  |_|  |_/_/\_\___|
 AV Linux MX Edition
Me@Desktop:~
$ Ardour6
Ardour6.6.0 (built using 6.6 and GCC version 6.3.0 20170516)
Ardour: [INFO]: Your system is configured to limit Ardour to 4096 open files
Ardour: [INFO]: Loading system configuration file /opt/Ardour-6.6.0/etc/system_config
Ardour: [INFO]: Loading user configuration file /home/Me/.config/ardour6/config
Ardour: [INFO]: CPU vendor: GenuineIntel
Ardour: [INFO]: CPU brand:               Intel(R) Pentium(R) 4 CPU 3.00GHz
Ardour: [INFO]: Using SSE optimized routines
Ardour: [INFO]: Loading plugin meta data file /opt/Ardour-6.6.0/share/plugin_metadata/plugin_tags
Ardour: [INFO]: Loading plugin statistics file /home/Me/.config/ardour6/plugin_metadata/plugin_stats
Cannot xinstall SIGPIPE error handler
Ardour: [INFO]: Loading default ui configuration file /opt/Ardour-6.6.0/etc/default_ui_config
Ardour: [INFO]: Loading user ui configuration file /home/Me/.config/ardour6/ui_config
Ardour: [INFO]: Loading 451 MIDI patches from /opt/Ardour-6.6.0/share/patchfiles
Ardour: [INFO]: Loading colour file /opt/Ardour-6.6.0/share/themes/dark-ardour.colors
Ardour: [INFO]: Loading ui configuration file /opt/Ardour-6.6.0/etc/clearlooks.rc
Ardour: [INFO]: Loading bindings from /opt/Ardour-6.6.0/etc/ardour.keys
Loading ui configuration file /opt/Ardour-6.6.0/etc/clearlooks.rc
Found nothing along /home/Me/.config/ardour6/templates:/opt/Ardour-6.6.0/share/templates
Scanning folders for bundled LV2s: /opt/Ardour-6.6.0/lib/LV2
Set cursor set to default
 loading from /media/Me/DATA/Ardour Projects/Untitled-2021-04-15-14-33-43 as Untitled-2021-04-15-14-33-43 templ urn:ardour:/opt/Ardour-6.6.0/share/scripts/session_template_record.lua is_new 1 bp 2
 
(ardour-6.6.0:3602): Gtk-CRITICAL **: IA__gtk_widget_event: assertion 'WIDGET_REALIZED_FOR_EVENT (widget, event)' failed
Starting disk thread...OK
EQ support: no
Stopping disk thread...terminate called without an active exception
Aborted
Me@Desktop:~
$ watched PID no longer exists - releasing device.

Any help would be much appreciated.

Thank you Paul, here are the results using Option 1: Running Ardour inside GDB.

Just one thing, was I right to assume that this isn’t necessary if using ALSA?

    ___   ___       __  ____  _____ 
   /_\ \ / / |  ___|  \/  \ \/ / __|
  / _ \ V /| |_|___| |\/| |>  <| _| 
 /_/ \_\_/ |____|  |_|  |_/_/\_\___|
 AV Linux MX Edition
Me@Desktop:~
$ /opt/Ardour_6.6.0/bin/ardour6 --gdb
bash: /opt/Ardour_6.6.0/bin/ardour6: No such file or directory
Me@Desktop:~
$ /opt/Ardour-6.6.0/bin/ardour6 --gdb
GNU gdb (Debian 8.2.1-2+b3) 8.2.1
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from /opt/Ardour-6.6.0/bin/ardour-6.6.0...(no debugging symbols found)...done.
(gdb) handle SIG32 noprint nostop
Signal        Stop	Print	Pass to program	Description
SIG32         No	No	Yes		Real-time event 32
(gdb) run
Starting program: /opt/Ardour-6.6.0/bin/ardour-6.6.0 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Ardour6.6.0 (built using 6.6 and GCC version 6.3.0 20170516)
Ardour: [INFO]: Your system is configured to limit Ardour to 4096 open files
Ardour: [INFO]: Loading system configuration file /opt/Ardour-6.6.0/etc/system_config
Ardour: [INFO]: Loading user configuration file /home/Me/.config/ardour6/config
[New Thread 0x7fffe5c65700 (LWP 5042)]
Ardour: [INFO]: CPU vendor: GenuineIntel
Ardour: [INFO]: CPU brand:               Intel(R) Pentium(R) 4 CPU 3.00GHz
Ardour: [INFO]: Using SSE optimized routines
[New Thread 0x7fffe5464700 (LWP 5043)]
[New Thread 0x7fffe4c63700 (LWP 5044)]
[New Thread 0x7fffdffff700 (LWP 5045)]
Ardour: [INFO]: Loading plugin meta data file /opt/Ardour-6.6.0/share/plugin_metadata/plugin_tags
Ardour: [INFO]: Loading plugin statistics file /home/Me/.config/ardour6/plugin_metadata/plugin_stats
[New Thread 0x7fffde421700 (LWP 5046)]
[Thread 0x7fffde421700 (LWP 5046) exited]
[New Thread 0x7fffde421700 (LWP 5047)]
[New Thread 0x7fffd3fff700 (LWP 5048)]
[New Thread 0x7fffd2753700 (LWP 5049)]
Cannot xinstall SIGPIPE error handler
Ardour: [INFO]: Loading default ui configuration file /opt/Ardour-6.6.0/etc/default_ui_config
Ardour: [INFO]: Loading user ui configuration file /home/Me/.config/ardour6/ui_config
Ardour: [INFO]: Loading 451 MIDI patches from /opt/Ardour-6.6.0/share/patchfiles
Ardour: [INFO]: Loading colour file /opt/Ardour-6.6.0/share/themes/dark-ardour.colors
Ardour: [INFO]: Loading ui configuration file /opt/Ardour-6.6.0/etc/clearlooks.rc
Ardour: [INFO]: Loading bindings from /opt/Ardour-6.6.0/etc/ardour.keys
Loading ui configuration file /opt/Ardour-6.6.0/etc/clearlooks.rc
[New Thread 0x7fffd1bfa700 (LWP 5050)]
[New Thread 0x7fffd1b79700 (LWP 5051)]
[Thread 0x7fffd1b79700 (LWP 5051) exited]
[New Thread 0x7fffd1b79700 (LWP 5053)]
[New Thread 0x7fffd0f5b700 (LWP 5054)]
[New Thread 0x7fffbffff700 (LWP 5055)]
[New Thread 0x7fffbf7fe700 (LWP 5056)]
Found nothing along /home/Me/.config/ardour6/templates:/opt/Ardour-6.6.0/share/templates
[Thread 0x7fffd1bfa700 (LWP 5050) exited]
[Thread 0x7fffbf7fe700 (LWP 5056) exited]
[Thread 0x7fffd0f5b700 (LWP 5054) exited]
[Thread 0x7fffd2753700 (LWP 5049) exited]
[New Thread 0x7fffd0f5b700 (LWP 5072)]
[Thread 0x7fffd0f5b700 (LWP 5072) exited]
[Detaching after vfork from child process 5073]
[New Thread 0x7fffd0f5b700 (LWP 5074)]
[New Thread 0x7fffd06e6900 (LWP 5075)]
[New Thread 0x7fffd06da900 (LWP 5076)]
[New Thread 0x7fffd06ce900 (LWP 5077)]
[New Thread 0x7fffd06c2900 (LWP 5078)]
[New Thread 0x7fffd05d6900 (LWP 5079)]
[New Thread 0x7fffbf7fe700 (LWP 5080)]
Scanning folders for bundled LV2s: /opt/Ardour-6.6.0/lib/LV2
[Thread 0x7fffbffff700 (LWP 5055) exited]
[New Thread 0x7fffbffff700 (LWP 5087)]
[New Thread 0x7fffbeffd700 (LWP 5088)]
[Thread 0x7fffbeffd700 (LWP 5088) exited]
[Detaching after vfork from child process 5089]
[New Thread 0x7fffbeffd700 (LWP 5090)]
[Thread 0x7fffbeffd700 (LWP 5090) exited]
[Detaching after vfork from child process 5091]
[New Thread 0x7fffbeffd700 (LWP 5092)]
[Thread 0x7fffbeffd700 (LWP 5092) exited]
Set cursor set to default
 loading from /media/Me/DATA/Ardour Projects/Untitled-2021-04-15-18-03-32 as Untitled-2021-04-15-18-03-32 templ urn:ardour:/opt/Ardour-6.6.0/share/scripts/session_template_record.lua is_new 1 bp 2
[New Thread 0x7fffd0039900 (LWP 5093)]
[New Thread 0x7fffd002d900 (LWP 5094)]
[New Thread 0x7fffbe7fb900 (LWP 5095)]
[New Thread 0x7fffbe7d7900 (LWP 5096)]
[New Thread 0x7fffbe7b4700 (LWP 5097)]
[New Thread 0x7fffbeffd700 (LWP 5098)]
[New Thread 0x7fffbcf30700 (LWP 5099)]
[New Thread 0x7fffb7fff700 (LWP 5100)]
[New Thread 0x7fffb77fe700 (LWP 5101)]
[New Thread 0x7fffb6ffd700 (LWP 5102)]
[Thread 0x7fffbffff700 (LWP 5087) exited]
[New Thread 0x7fffbc5dd700 (LWP 5117)]
[New Thread 0x7fffbc55c700 (LWP 5118)]
Starting disk thread...[New Thread 0x7fffbc4db700 (LWP 5119)]
OK
EQ support: no
Stopping disk thread...terminate called without an active exception

Thread 40 "ArdourGUI" received signal SIGABRT, Aborted.
[Switching to Thread 0x7fffbc4db700 (LWP 5119)]
__GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
50	../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) thread apply all bt

Thread 40 (Thread 0x7fffbc4db700 (LWP 5119)):
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x00007fffee44b535 in __GI_abort () at abort.c:79
#2  0x00007fffee841983 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
#3  0x00007fffee8478c6 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
#4  0x00007fffee847901 in std::terminate() () from /lib/x86_64-linux-gnu/libstdc++.so.6
#5  0x00007fffee847324 in __gxx_personality_v0 () from /lib/x86_64-linux-gnu/libstdc++.so.6
#6  0x00007fffee5fcf28 in ?? () from /lib/x86_64-linux-gnu/libgcc_s.so.1
#7  0x00007fffee5fd51c in _Unwind_ForcedUnwind () from /lib/x86_64-linux-gnu/libgcc_s.so.1
#8  0x00007ffff09010a0 in __GI___pthread_unwind (buf=<optimized out>) at unwind.c:121
#9  0x00007ffff08f673a in __do_cancel () at ./pthreadP.h:305
#10 sigcancel_handler (sig=32, si=0x7fffbc4da970, ctx=<optimized out>) at nptl-init.c:200
#11 sigcancel_handler (sig=<optimized out>, si=0x7fffbc4da970, ctx=<optimized out>)
    at nptl-init.c:165
#12 <signal handler called>
#13 __lll_unlock_wake () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:339
#14 0x00007ffff08fbee2 in __pthread_mutex_unlock_usercnt (mutex=0x55555a2cf498, 
    decr=<optimized out>) at pthread_mutex_unlock.c:56
#15 0x00007fffb61c76da in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#16 0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#17 0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 39 (Thread 0x7fffbc55c700 (LWP 5118)):
#0  0x00007fffee4ef720 in __GI___nanosleep (requested_time=requested_time@entry=0x7fffbc55bcd0, 
    remaining=remaining@entry=0x7fffbc55bcd0) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
#1  0x00007fffee4ef62a in __sleep (seconds=0) at ../sysdeps/posix/sleep.c:55
--Type <RET> for more, q to quit, c to continue without paging--
#2  0x00007fffb619afaa in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#3  0x00007fffb61c76e3 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#4  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 38 (Thread 0x7fffbc5dd700 (LWP 5117)):
#0  0x00007fffee51a037 in __GI___select (nfds=43, readfds=0x7fffbc5dcc50, writefds=0x0, 
    exceptfds=0x0, timeout=0x7fffbc5dcba0) at ../sysdeps/unix/sysv/linux/select.c:41
#1  0x00007fffb61ece8b in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#2  0x00007fffb61c76e3 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#3  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 37 (Thread 0x7fffb6ffd700 (LWP 5102)):
#0  0x00007ffff0901bf0 in __GI___nanosleep (requested_time=0x7fffb6ffccc0, 
    remaining=0x7fffb6ffccd0) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
#1  0x00007ffff481ba38 in g_usleep () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x00007ffff70eddc0 in ARDOUR::AutomationWatch::thread() ()
   from /opt/Ardour-6.6.0/lib/libardour.so.3
#3  0x00007ffff4d84c4d in ?? () from /opt/Ardour-6.6.0/lib/libglibmm-2.4.so.1
#4  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 36 (Thread 0x7fffb77fe700 (LWP 5101)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x55555cce4150)
    at ../sysdeps/unix/sysv/linux/futex-internal.h:88
--Type <RET> for more, q to quit, c to continue without paging--
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x55555cce4100, cond=0x55555cce4128)
    at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x55555cce4128, mutex=0x55555cce4100) at pthread_cond_wait.c:655
#3  0x00007ffff7521bc3 in ARDOUR::Session::auto_connect_thread_run() ()
   from /opt/Ardour-6.6.0/lib/libardour.so.3
#4  0x00007ffff7521d98 in ARDOUR::Session::auto_connect_thread(void*) ()
   from /opt/Ardour-6.6.0/lib/libardour.so.3
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 35 (Thread 0x7fffb7fff700 (LWP 5100)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x55555cce40e0)
    at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x55555cce4090, cond=0x55555cce40b8)
    at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x55555cce40b8, mutex=0x55555cce4090) at pthread_cond_wait.c:655
#3  0x00007ffff75963f3 in ARDOUR::Session::emit_thread_run() ()
   from /opt/Ardour-6.6.0/lib/libardour.so.3
#4  0x00007ffff7596428 in ARDOUR::Session::emit_thread(void*) ()
   from /opt/Ardour-6.6.0/lib/libardour.so.3
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 34 (Thread 0x7fffbcf30700 (LWP 5099)):
#0  0x00007fffee517819 in __GI___poll (fds=0x7fffc0005750, nfds=2, timeout=-1)
    at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ffff47ead66 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
--Type <RET> for more, q to quit, c to continue without paging--c
#2  0x00007ffff47eb0f2 in g_main_loop_run () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#3  0x00007ffff5966a28 in BaseUI::main_thread() () from /opt/Ardour-6.6.0/lib/libpbd.so.4
#4  0x00007ffff4d84c4d in ?? () from /opt/Ardour-6.6.0/lib/libglibmm-2.4.so.1
#5  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#6  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#7  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 33 (Thread 0x7fffbeffd700 (LWP 5098)):
#0  0x00007fffee517819 in __GI___poll (fds=0x7fffc5fe7450, nfds=4, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ffff47ead66 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x00007ffff47eb0f2 in g_main_loop_run () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#3  0x00007ffff5966a28 in BaseUI::main_thread() () from /opt/Ardour-6.6.0/lib/libpbd.so.4
#4  0x00007ffff4d84c4d in ?? () from /opt/Ardour-6.6.0/lib/libglibmm-2.4.so.1
#5  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#6  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#7  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 32 (Thread 0x7fffbe7b4700 (LWP 5097)):
#0  0x00007fffee517819 in __GI___poll (fds=0x7fffbe7b3ae8, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ffff5970d57 in CrossThreadChannel::poll_for_request() () from /opt/Ardour-6.6.0/lib/libpbd.so.4
#2  0x00007ffff5970db6 in CrossThreadChannel::receive(char&, bool) () from /opt/Ardour-6.6.0/lib/libpbd.so.4
#3  0x00007ffff70fb532 in ARDOUR::Butler::thread_work() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#4  0x00007ffff70fc692 in ARDOUR::Butler::_thread_work(void*) () from /opt/Ardour-6.6.0/lib/libardour.so.3
#5  0x00007ffff5999996 in ?? () from /opt/Ardour-6.6.0/lib/libpbd.so.4
#6  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#7  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 31 (Thread 0x7fffbe7d7900 (LWP 5096)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, futex_word=0x55555ccf6cc0) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  do_futex_wait (sem=sem@entry=0x55555ccf6cc0, abstime=0x0) at sem_waitcommon.c:111
#2  0x00007ffff0900988 in __new_sem_wait_slow (sem=0x55555ccf6cc0, abstime=0x0) at sem_waitcommon.c:181
#3  0x00007ffff71c602c in ARDOUR::Graph::run_one() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#4  0x00007ffff71c6348 in ARDOUR::Graph::helper_thread() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#5  0x00007fffd318c666 in ARDOUR::AlsaAudioBackend::alsa_process_thread(void*) () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#6  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#7  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 30 (Thread 0x7fffbe7fb900 (LWP 5095)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, futex_word=0x55555ccf6ce8) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  do_futex_wait (sem=sem@entry=0x55555ccf6ce8, abstime=0x0) at sem_waitcommon.c:111
#2  0x00007ffff0900988 in __new_sem_wait_slow (sem=0x55555ccf6ce8, abstime=0x0) at sem_waitcommon.c:181
#3  0x00007ffff71c5f46 in ARDOUR::Graph::reached_terminal_node() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#4  0x00007ffff71c6630 in ARDOUR::Graph::main_thread() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#5  0x00007fffd318c666 in ARDOUR::AlsaAudioBackend::alsa_process_thread(void*) () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#6  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#7  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 29 (Thread 0x7fffd002d900 (LWP 5094)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, futex_word=0x55555c79b1b0) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  do_futex_wait (sem=sem@entry=0x55555c79b1b0, abstime=0x0) at sem_waitcommon.c:111
#2  0x00007ffff0900988 in __new_sem_wait_slow (sem=0x55555c79b1b0, abstime=0x0) at sem_waitcommon.c:181
#3  0x00007ffff7508439 in ARDOUR::RTTaskList::run() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#4  0x00007ffff7508858 in ARDOUR::RTTaskList::_thread_run(void*) () from /opt/Ardour-6.6.0/lib/libardour.so.3
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 28 (Thread 0x7fffd0039900 (LWP 5093)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, futex_word=0x55555c79b1b0) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  do_futex_wait (sem=sem@entry=0x55555c79b1b0, abstime=0x0) at sem_waitcommon.c:111
#2  0x00007ffff0900988 in __new_sem_wait_slow (sem=0x55555c79b1b0, abstime=0x0) at sem_waitcommon.c:181
#3  0x00007ffff7508439 in ARDOUR::RTTaskList::run() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#4  0x00007ffff7508858 in ARDOUR::RTTaskList::_thread_run(void*) () from /opt/Ardour-6.6.0/lib/libardour.so.3
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 23 (Thread 0x7fffbf7fe700 (LWP 5080)):
#0  0x00007fffee517819 in __GI___poll (fds=0x7fffb800d250, nfds=1, timeout=200) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fffd318fc94 in ARDOUR::AlsaAudioBackend::midi_device_thread() () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#2  0x00007fffd318fce9 in ARDOUR::AlsaAudioBackend::_midi_device_thread(void*) () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#3  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 22 (Thread 0x7fffd05d6900 (LWP 5079)):
#0  0x00007fffee517916 in __GI_ppoll (fds=0x55555734b7dc, nfds=2, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007fffd31a7fbd in Alsa_pcmi::pcm_wait() () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#2  0x00007fffd3191aca in ARDOUR::AlsaAudioBackend::main_process_thread() () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#3  0x00007fffd3192b49 in ?? () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#4  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 21 (Thread 0x7fffd06c2900 (LWP 5078)):
#0  0x00007fffee517819 in __GI___poll (fds=0x55555733c4a0, nfds=1, timeout=100) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fffd31a15d8 in ARDOUR::AlsaRawMidiIn::main_process_thread() () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#2  0x00007fffd319fae9 in ?? () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#3  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 20 (Thread 0x7fffd06ce900 (LWP 5077)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x555556ad9478) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x555556ad9428, cond=0x555556ad9450) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x555556ad9450, mutex=0x555556ad9428) at pthread_cond_wait.c:655
#3  0x00007fffd31a19ae in ARDOUR::AlsaRawMidiOut::main_process_thread() () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#4  0x00007fffd319fae9 in ?? () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 19 (Thread 0x7fffd06da900 (LWP 5076)):
#0  0x00007fffee517819 in __GI___poll (fds=0x555556b0ef10, nfds=1, timeout=100) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fffd31a15d8 in ARDOUR::AlsaRawMidiIn::main_process_thread() () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#2  0x00007fffd319fae9 in ?? () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#3  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 18 (Thread 0x7fffd06e6900 (LWP 5075)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x555556a88878) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x555556a88828, cond=0x555556a88850) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x555556a88850, mutex=0x555556a88828) at pthread_cond_wait.c:655
#3  0x00007fffd31a19ae in ARDOUR::AlsaRawMidiOut::main_process_thread() () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#4  0x00007fffd319fae9 in ?? () from /opt/Ardour-6.6.0/lib/backends/libalsa_audiobackend.so
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 17 (Thread 0x7fffd0f5b700 (LWP 5074)):
#0  0x00007fffee51a037 in __GI___select (nfds=1, readfds=0x7fffd0f58c70, writefds=0x0, exceptfds=0x0, timeout=0x7fffd0f58c50) at ../sysdeps/unix/sysv/linux/select.c:41
#1  0x00007ffff59a9d86 in PBD::SystemExec::output_interposer() () from /opt/Ardour-6.6.0/lib/libpbd.so.4
#2  0x00007ffff59a9f08 in ?? () from /opt/Ardour-6.6.0/lib/libpbd.so.4
#3  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 12 (Thread 0x7fffd1b79700 (LWP 5053)):
#0  0x00007fffee517819 in __GI___poll (fds=0x555556e9d150, nfds=2, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ffff47ead66 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x00007ffff47eae7c in g_main_context_iteration () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#3  0x00007ffff47eaec1 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#4  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7fffd3fff700 (LWP 5048)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff483be4c in g_cond_wait () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x00007ffff70a7d83 in ARDOUR::AudioEngine::do_devicelist_update() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#3  0x00007ffff4d84c4d in ?? () from /opt/Ardour-6.6.0/lib/libglibmm-2.4.so.1
#4  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7fffde421700 (LWP 5047)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff483be4c in g_cond_wait () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x00007ffff70a9e95 in ARDOUR::AudioEngine::do_reset_backend() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#3  0x00007ffff4d84c4d in ?? () from /opt/Ardour-6.6.0/lib/libglibmm-2.4.so.1
#4  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7fffdffff700 (LWP 5045)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff483be4c in g_cond_wait () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x00007ffff7068ff7 in ARDOUR::Analyser::work() () from /opt/Ardour-6.6.0/lib/libardour.so.3
#3  0x00007ffff4d84c4d in ?? () from /opt/Ardour-6.6.0/lib/libglibmm-2.4.so.1
#4  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7fffe4c63700 (LWP 5044)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff483be4c in g_cond_wait () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x00007ffff76060c7 in ?? () from /opt/Ardour-6.6.0/lib/libardour.so.3
#3  0x00007ffff4d84c4d in ?? () from /opt/Ardour-6.6.0/lib/libglibmm-2.4.so.1
#4  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7fffe5464700 (LWP 5043)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff483be4c in g_cond_wait () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x00007ffff76060c7 in ?? () from /opt/Ardour-6.6.0/lib/libardour.so.3
#3  0x00007ffff4d84c4d in ?? () from /opt/Ardour-6.6.0/lib/libglibmm-2.4.so.1
#4  0x00007ffff481a1e5 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#5  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7fffe5c65700 (LWP 5042)):
#0  0x00007ffff0901bf0 in __GI___nanosleep (requested_time=0x7fffe5c64b40, remaining=0x7fffe5c64b50) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
#1  0x00007ffff481ba38 in g_usleep () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#2  0x000055555622428b in ?? ()
#3  0x00007ffff08f7fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffee5224cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7fffea20b900 (LWP 5038)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x55555a2cf520) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x55555a2cf498, cond=0x55555a2cf4f8) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x55555a2cf4f8, mutex=0x55555a2cf498) at pthread_cond_wait.c:655
#3  0x00007fffb622e144 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#4  0x00007fffb61c737d in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#5  0x00007fffb6259dc3 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#6  0x00007fffb625a16b in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#7  0x00007fffb62f8870 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#8  0x00007fffb625cc6a in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#9  0x00007fffb61c7b83 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#10 0x00007fffb61ccec8 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#11 0x00007fffb619da4c in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#12 0x00007fffb619ddad in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#13 0x00007fffb6198d56 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#14 0x00007ffff0040234 in lilv_state_restore () from /opt/Ardour-6.6.0/lib/liblilv-0.so.0
#15 0x00007ffff767880b in ARDOUR::LV2Plugin::init(void const*, long) () from /opt/Ardour-6.6.0/lib/libardour.so.3
#16 0x00007ffff7679393 in ARDOUR::LV2Plugin::LV2Plugin(ARDOUR::AudioEngine&, ARDOUR::Session&, void const*, long) () from /opt/Ardour-6.6.0/lib/libardour.so.3
#17 0x00007ffff7679508 in ARDOUR::LV2PluginInfo::load(ARDOUR::Session&) () from /opt/Ardour-6.6.0/lib/libardour.so.3
#18 0x00007ffff752f1c6 in ARDOUR::Session::load_and_connect_instruments(std::__cxx11::list<boost::shared_ptr<ARDOUR::Route>, std::allocator<boost::shared_ptr<ARDOUR::Route> > >&, bool, boost::shared_ptr<ARDOUR::PluginInfo>, ARDOUR::Plugin::PresetRecord*, ARDOUR::ChanCount&) () from /opt/Ardour-6.6.0/lib/libardour.so.3
#19 0x00007ffff7536ba8 in ARDOUR::Session::new_midi_track(ARDOUR::ChanCount const&, ARDOUR::ChanCount const&, bool, boost::shared_ptr<ARDOUR::PluginInfo>, ARDOUR::Plugin::PresetRecord*, ARDOUR::RouteGroup*, unsigned int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, unsigned int, ARDOUR::TrackMode, bool) () from /opt/Ardour-6.6.0/lib/libardour.so.3
#20 0x000055555595829a in ?? ()
#21 0x000055555595a185 in ?? ()
#22 0x00007ffff1f2a5f5 in ?? () from /opt/Ardour-6.6.0/lib/libgtkmm-2.4.so.1
#23 0x00007ffff4af9945 in g_closure_invoke () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#24 0x00007ffff4b0b01b in ?? () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#25 0x00007ffff4b14c30 in g_signal_emit_valist () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#26 0x00007ffff4b15082 in g_signal_emit () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#27 0x00007ffff3d380d4 in ?? () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#28 0x00007ffff4af9b74 in ?? () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#29 0x00007ffff4b14904 in g_signal_emit_valist () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#30 0x00007ffff4b15082 in g_signal_emit () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#31 0x00007ffff3cf6d82 in ?? () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#32 0x00007ffff4af9b74 in ?? () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#33 0x00007ffff4b14904 in g_signal_emit_valist () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#34 0x00007ffff4b15082 in g_signal_emit () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#35 0x00007ffff3cf4f92 in gtk_button_released () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#36 0x00007ffff3cf5059 in ?? () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#37 0x00007ffff3dddcac in ?? () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#38 0x00007ffff4af9945 in g_closure_invoke () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#39 0x00007ffff4b0b5a0 in ?? () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#40 0x00007ffff4b1469b in g_signal_emit_valist () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#41 0x00007ffff4b15082 in g_signal_emit () from /opt/Ardour-6.6.0/lib/libgobject-2.0.so.0
#42 0x00007ffff3f6264c in ?? () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#43 0x00007ffff3ddc29d in gtk_propagate_event () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#44 0x00007ffff3ddc723 in gtk_main_do_event () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#45 0x00007ffff39f8b4c in ?? () from /opt/Ardour-6.6.0/lib/libgdk-x11-2.0.so.0
#46 0x00007ffff47eab67 in g_main_context_dispatch () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#47 0x00007ffff47eadd0 in ?? () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#48 0x00007ffff47eb0f2 in g_main_loop_run () from /opt/Ardour-6.6.0/lib/libglib-2.0.so.0
#49 0x00007ffff3ddb3e7 in gtk_main () from /opt/Ardour-6.6.0/lib/libgtk-x11-2.0.so.0
#50 0x00007ffff5c35a45 in Gtkmm2ext::UI::run(Receiver&) () from /opt/Ardour-6.6.0/lib/libgtkmm2ext.so.0
#51 0x00005555559184db in ?? ()
#52 0x00007fffee44d09b in __libc_start_main (main=0x5555559180e0, argc=1, argv=0x7fffffffd5b8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffd5a8) at ../csu/libc-start.c:308
#53 0x000055555591ec2a in ?? ()
(gdb) 

This really needs a debug build to be useful. You can get one from nightly.ardour.org

It looks likely that the crash is caused by LinuxSampler. Two notes on that: (1) unless you specifically plan to use a sample library in a format only supported by LS, we generally recommend that people use SFZ or SF2 plugins (such as sfizz for SFZ and fluidsynth for SF2) in preference to LS. (2) mentioning that a plugin does not crash in one host is generally not helpful or indicative of anything (oddly though, the opposite is useful!)

Thanks for the advice Paul.

Anyway, after installing Ardour-6.6.291-dbg-x86_64-gcc5.run, here’s the backtrace.

    ___   ___       __  ____  _____ 
   /_\ \ / / |  ___|  \/  \ \/ / __|
  / _ \ V /| |_|___| |\/| |>  <| _| 
 /_/ \_\_/ |____|  |_|  |_/_/\_\___|
 AV Linux MX Edition
Me@Desktop:~
$ /opt/Ardour-6.6.291-dbg/bin/ardour6 --gdb
GNU gdb (Debian 8.2.1-2+b3) 8.2.1
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from /opt/Ardour-6.6.291-dbg/bin/ardour-6.6.291...done.
(gdb) handle SIG32 noprint nostop
Signal        Stop	Print	Pass to program	Description
SIG32         No	No	Yes		Real-time event 32
(gdb) run
Starting program: /opt/Ardour-6.6.291-dbg/bin/ardour-6.6.291 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
bind txt domain [gtk2_ardour6] to /opt/Ardour-6.6.291-dbg/share/locale
Ardour6.6.291 (built using 6.6-291-g725c00236c and GCC version 6.3.0 20170516)
Ardour: [INFO]: Your system is configured to limit Ardour to 4096 open files
Ardour: [INFO]: Loading system configuration file /opt/Ardour-6.6.291-dbg/etc/system_config
Ardour: [INFO]: Loading user configuration file /home/Me/.config/ardour6/config
[New Thread 0x7fffe43bc700 (LWP 5643)]
Ardour: [INFO]: CPU vendor: GenuineIntel
Ardour: [INFO]: CPU brand:               Intel(R) Pentium(R) 4 CPU 3.00GHz
Ardour: [INFO]: Using SSE optimized routines
[New Thread 0x7fffe3bbb700 (LWP 5644)]
[New Thread 0x7fffe33ba700 (LWP 5645)]
[New Thread 0x7fffe2bb9700 (LWP 5646)]
Ardour: [INFO]: Loading plugin meta data file /opt/Ardour-6.6.291-dbg/share/plugin_metadata/plugin_tags
Ardour: [INFO]: Loading plugin statistics file /home/Me/.config/ardour6/plugin_metadata/plugin_stats
[New Thread 0x7fffcffff700 (LWP 5662)]
[Thread 0x7fffcffff700 (LWP 5662) exited]
[New Thread 0x7fffcffff700 (LWP 5664)]
[New Thread 0x7fffcd90d700 (LWP 5665)]
*** WEAK-JACK: initializing
*** WEAK-JACK: OK. (0)
[New Thread 0x7fffc7886700 (LWP 5666)]
Cannot xinstall SIGPIPE error handler
Ardour: [INFO]: Loading default ui configuration file /opt/Ardour-6.6.291-dbg/etc/default_ui_config
Ardour: [INFO]: Loading user ui configuration file /home/Me/.config/ardour6/ui_config
Ardour: [INFO]: Loading 451 MIDI patches from /opt/Ardour-6.6.291-dbg/share/patchfiles
Ardour: [INFO]: Loading colour file /opt/Ardour-6.6.291-dbg/share/themes/dark-ardour.colors
Ardour: [INFO]: Loading ui configuration file /opt/Ardour-6.6.291-dbg/etc/clearlooks.rc
Ardour: [INFO]: Loading bindings from /opt/Ardour-6.6.291-dbg/etc/ardour.keys
Loading ui configuration file /opt/Ardour-6.6.291-dbg/etc/clearlooks.rc
[New Thread 0x7fffc6d26700 (LWP 5667)]
[New Thread 0x7fffc6ca5700 (LWP 5668)]
[Thread 0x7fffc6ca5700 (LWP 5668) exited]
[New Thread 0x7fffc6ca5700 (LWP 5669)]
pingback: No Error
[Thread 0x7fffc6d26700 (LWP 5667) exited]
[New Thread 0x7fffc60df700 (LWP 5670)]
[New Thread 0x7fffc58de700 (LWP 5671)]
Found nothing along /home/Me/.config/ardour6/templates:/opt/Ardour-6.6.291-dbg/share/templates
[Thread 0x7fffc60df700 (LWP 5670) exited]
[Thread 0x7fffc7886700 (LWP 5666) exited]
[Thread 0x7fffc58de700 (LWP 5671) exited]
[New Thread 0x7fffc58de700 (LWP 5733)]
[New Thread 0x7fffc60df700 (LWP 5734)]
[New Thread 0x7fffc4faa700 (LWP 5735)]
[New Thread 0x7fffbbfff700 (LWP 5736)]
[New Thread 0x7fffbb7fe700 (LWP 5737)]
[New Thread 0x7fffbaffd700 (LWP 5738)]
[New Thread 0x7fffba7fc700 (LWP 5739)]
[New Thread 0x7fffb9ffb700 (LWP 5740)]
[Thread 0x7fffbaffd700 (LWP 5738) exited]
[Thread 0x7fffbb7fe700 (LWP 5737) exited]
[Thread 0x7fffc60df700 (LWP 5734) exited]
[Thread 0x7fffbbfff700 (LWP 5736) exited]
[Thread 0x7fffc4faa700 (LWP 5735) exited]
[Thread 0x7fffba7fc700 (LWP 5739) exited]
[Thread 0x7fffb9ffb700 (LWP 5740) exited]
[Thread 0x7fffc58de700 (LWP 5733) exited]
[Detaching after vfork from child process 5821]
[New Thread 0x7fffc58de700 (LWP 5822)]
 --[[ ALSA Device hw:Crimson,0
playback
  nchan  : 2
  fsamp  : 48000
  fsize  : 512
  nfrag  : 3
  format : S24_3LE
capture
  nchan  : 2
  fsamp  : 48000
  fsize  : 512
  nfrag  : 3
  format : S24_3LE
synced
 --]]
[New Thread 0x7fffcc00a900 (LWP 5823)]
[New Thread 0x7fffc60de900 (LWP 5824)]
[New Thread 0x7fffc60d2900 (LWP 5825)]
[New Thread 0x7fffc60c6900 (LWP 5826)]
[New Thread 0x7fffc60ba900 (LWP 5827)]
[New Thread 0x7fffb9ffb700 (LWP 5828)]
Scanning folders for bundled LV2s: /opt/Ardour-6.6.291-dbg/lib/LV2
[New Thread 0x7fffba7fc700 (LWP 5843)]
[New Thread 0x7fffc4faa700 (LWP 5844)]
[Thread 0x7fffc4faa700 (LWP 5844) exited]
[Detaching after vfork from child process 5845]
[New Thread 0x7fffc4faa700 (LWP 5846)]
[Thread 0x7fffc4faa700 (LWP 5846) exited]
[Detaching after vfork from child process 5852]
[New Thread 0x7fffc4faa700 (LWP 5853)]
[Thread 0x7fffc4faa700 (LWP 5853) exited]
Set cursor set to default
 loading from /media/Me/DATA/Ardour Projects/Untitled-2021-04-16-15-09-07 as Untitled-2021-04-16-15-09-07 templ urn:ardour:/opt/Ardour-6.6.291-dbg/share/scripts/session_template_record.lua is_new 1 bp 2
[New Thread 0x7fffc5a2a900 (LWP 5854)]
[New Thread 0x7fffc5a1e900 (LWP 5855)]
[New Thread 0x7fffc5a12900 (LWP 5856)]
[New Thread 0x7fffc598e900 (LWP 5857)]
[New Thread 0x7fffc47a9700 (LWP 5858)]
[New Thread 0x7fffc4faa700 (LWP 5859)]
[New Thread 0x7fffb97fa700 (LWP 5860)]
[New Thread 0x7fffb8ff9700 (LWP 5861)]
[New Thread 0x7fffb3fff700 (LWP 5862)]
actually writing state to /media/Me/DATA/Ardour Projects/Untitled-2021-04-16-15-09-07/Untitled-2021-04-16-15-09-07.tmp
renaming state to /media/Me/DATA/Ardour Projects/Untitled-2021-04-16-15-09-07/Untitled-2021-04-16-15-09-07.ardour
saved state in 35.2 ms
locate to 0 took 388 usecs for 1 tracks = 388 per track
[New Thread 0x7fffb37fe700 (LWP 5863)]
actually writing state to /media/Me/DATA/Ardour Projects/Untitled-2021-04-16-15-09-07/Untitled-2021-04-16-15-09-07.tmp
renaming state to /media/Me/DATA/Ardour Projects/Untitled-2021-04-16-15-09-07/Untitled-2021-04-16-15-09-07.ardour
saved state in 8.1 ms
actually writing state to /media/Me/DATA/Ardour Projects/Untitled-2021-04-16-15-09-07/Untitled-2021-04-16-15-09-07.tmp
renaming state to /media/Me/DATA/Ardour Projects/Untitled-2021-04-16-15-09-07/Untitled-2021-04-16-15-09-07.ardour
saved state in 13.7 ms

(ardour-6.6.291:5630): Gtk-WARNING **: gtk_widget_size_allocate(): attempt to allocate widget with width -3 and height -3

(ardour-6.6.291:5630): Gtk-WARNING **: gtk_widget_size_allocate(): attempt to allocate widget with width -3 and height -3
[Thread 0x7fffba7fc700 (LWP 5843) exited]
[New Thread 0x7fffc45d6700 (LWP 5864)]
[New Thread 0x7fffc4555700 (LWP 5874)]
Starting disk thread...[New Thread 0x7fffc44d4700 (LWP 5875)]
OK
EQ support: no
Stopping disk thread...terminate called without an active exception

Thread 46 "ArdourGUI" received signal SIGABRT, Aborted.
[Switching to Thread 0x7fffc44d4700 (LWP 5875)]
__GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
50	../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) thread apply all bt

Thread 46 (Thread 0x7fffc44d4700 (LWP 5875)):
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x00007fffecbd0535 in __GI_abort () at abort.c:79
#2  0x00007fffecf98983 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
#3  0x00007fffecf9e8c6 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
#4  0x00007fffecf9e901 in std::terminate() () from /lib/x86_64-linux-gnu/libstdc++.so.6
#5  0x00007fffecf9e324 in __gxx_personality_v0 () from /lib/x86_64-linux-gnu/libstdc++.so.6
#6  0x00007fffecd7ff28 in ?? () from /lib/x86_64-linux-gnu/libgcc_s.so.1
#7  0x00007fffecd8051c in _Unwind_ForcedUnwind () from /lib/x86_64-linux-gnu/libgcc_s.so.1
#8  0x00007fffef0570a0 in __GI___pthread_unwind (buf=<optimized out>) at unwind.c:121
#9  0x00007fffef04c73a in __do_cancel () at ./pthreadP.h:305
#10 sigcancel_handler (sig=32, si=0x7fffc44d3970, ctx=<optimized out>) at nptl-init.c:200
#11 sigcancel_handler (sig=<optimized out>, si=0x7fffc44d3970, ctx=<optimized out>)
    at nptl-init.c:165
#12 <signal handler called>
#13 __lll_unlock_wake () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:339
#14 0x00007fffef051ee2 in __pthread_mutex_unlock_usercnt (mutex=0x555559046698, 
    decr=<optimized out>) at pthread_mutex_unlock.c:56
#15 0x00007fffb81c36da in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#16 0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#17 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 45 (Thread 0x7fffc4555700 (LWP 5874)):
#0  0x00007fffecc74720 in __GI___nanosleep (requested_time=requested_time@entry=0x7fffc4554cd0, 
    remaining=remaining@entry=0x7fffc4554cd0) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
#1  0x00007fffecc7462a in __sleep (seconds=0) at ../sysdeps/posix/sleep.c:55
--Type <RET> for more, q to quit, c to continue without paging--c
#2  0x00007fffb8196faa in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#3  0x00007fffb81c36e3 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#4  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 44 (Thread 0x7fffc45d6700 (LWP 5864)):
#0  0x00007fffecc9f037 in __GI___select (nfds=43, readfds=0x7fffc45d5c50, writefds=0x0, exceptfds=0x0, timeout=0x7fffc45d5ba0) at ../sysdeps/unix/sysv/linux/select.c:41
#1  0x00007fffb81e8e8b in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#2  0x00007fffb81c36e3 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#3  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 43 (Thread 0x7fffb37fe700 (LWP 5863)):
#0  0x00007fffef057bf0 in __GI___nanosleep (requested_time=0x7fffb37fdbb0, remaining=0x7fffb37fdbc0) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
#1  0x00007ffff2f71a38 in g_usleep () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff6a99544 in ARDOUR::AutomationWatch::thread (this=0x7fffd4123650) at ../libs/ardour/automation_watch.cc:195
#3  0x00007ffff6a9ed4b in boost::_mfi::mf0<void, ARDOUR::AutomationWatch>::operator() (this=0x555559e970a0, p=0x7fffd4123650) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/mem_fn_template.hpp:49
#4  0x00007ffff6a9e990 in boost::_bi::list1<boost::_bi::value<ARDOUR::AutomationWatch*> >::operator()<boost::_mfi::mf0<void, ARDOUR::AutomationWatch>, boost::_bi::list0> (this=0x555559e970b0, f=..., a=...) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:259
#5  0x00007ffff6a9e0b1 in boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AutomationWatch>, boost::_bi::list1<boost::_bi::value<ARDOUR::AutomationWatch*> > >::operator() (this=0x555559e970a0) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:1294
#6  0x00007ffff6a9e032 in sigc::adaptor_functor<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AutomationWatch>, boost::_bi::list1<boost::_bi::value<ARDOUR::AutomationWatch*> > > >::operator() (this=0x555559e970a0) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:256
#7  0x00007ffff6a9d890 in sigc::internal::slot_call0<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AutomationWatch>, boost::_bi::list1<boost::_bi::value<ARDOUR::AutomationWatch*> > >, void>::call_it (rep=0x555559e97070) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:103
#8  0x00007ffff34dac4d in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglibmm-2.4.so.1
#9  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#10 0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#11 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 42 (Thread 0x7fffb3fff700 (LWP 5862)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x55555cfcdebc) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x55555cfcde68, cond=0x55555cfcde90) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x55555cfcde90, mutex=0x55555cfcde68) at pthread_cond_wait.c:655
#3  0x00007ffff70d11b1 in ARDOUR::Session::auto_connect_thread_run (this=0x55555cfcbfe0) at ../libs/ardour/session.cc:7181
#4  0x00007ffff70d0cd8 in ARDOUR::Session::auto_connect_thread (arg=0x55555cfcbfe0) at ../libs/ardour/session.cc:7112
#5  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 41 (Thread 0x7fffb8ff9700 (LWP 5861)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x55555cfcde48) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x55555cfcddf8, cond=0x55555cfcde20) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x55555cfcde20, mutex=0x55555cfcddf8) at pthread_cond_wait.c:655
#3  0x00007ffff714b9a5 in ARDOUR::Session::emit_thread_run (this=0x55555cfcbfe0) at ../libs/ardour/session_process.cc:1114
#4  0x00007ffff714b942 in ARDOUR::Session::emit_thread (arg=0x55555cfcbfe0) at ../libs/ardour/session_process.cc:1103
#5  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 40 (Thread 0x7fffb97fa700 (LWP 5860)):
#0  0x00007fffecc9c819 in __GI___poll (fds=0x55555c01b380, nfds=2, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ffff2f40d66 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff2f410f2 in g_main_loop_run () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#3  0x00007ffff417ab46 in BaseUI::main_thread (this=0x55555cf4b400) at ../libs/pbd/base_ui.cc:98
#4  0x00007ffff417ec68 in sigc::bound_mem_functor0<void, BaseUI>::operator() (this=0x55555c00e078) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/mem_fun.h:1787
#5  0x00007ffff417e8a8 in sigc::adaptor_functor<sigc::bound_mem_functor0<void, BaseUI> >::operator() (this=0x55555c00e070) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:256
#6  0x00007ffff417e2e9 in sigc::internal::slot_call0<sigc::bound_mem_functor0<void, BaseUI>, void>::call_it (rep=0x55555c00e040) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:103
#7  0x00007ffff34dac4d in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglibmm-2.4.so.1
#8  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#9  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#10 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 39 (Thread 0x7fffc4faa700 (LWP 5859)):
#0  0x00007fffecc9c819 in __GI___poll (fds=0x7fffdc17e0f0, nfds=4, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ffff2f40d66 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff2f410f2 in g_main_loop_run () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#3  0x00007ffff417ab46 in BaseUI::main_thread (this=0x55555d66fe10) at ../libs/pbd/base_ui.cc:98
#4  0x00007ffff417ec68 in sigc::bound_mem_functor0<void, BaseUI>::operator() (this=0x555558007488) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/mem_fun.h:1787
#5  0x00007ffff417e8a8 in sigc::adaptor_functor<sigc::bound_mem_functor0<void, BaseUI> >::operator() (this=0x555558007480) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:256
#6  0x00007ffff417e2e9 in sigc::internal::slot_call0<sigc::bound_mem_functor0<void, BaseUI>, void>::call_it (rep=0x555558007450) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:103
#7  0x00007ffff34dac4d in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglibmm-2.4.so.1
#8  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#9  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#10 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 38 (Thread 0x7fffc47a9700 (LWP 5858)):
#0  0x00007fffecc9c819 in __GI___poll (fds=0x7fffc47a8328, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ffff41909f8 in CrossThreadChannel::poll_for_request (this=0x5555593737c8) at ../libs/pbd/crossthread.posix.cc:102
#2  0x00007ffff4190a61 in CrossThreadChannel::receive (this=0x5555593737c8, msg=@0x7fffc47a83ef: 0 '\000', wait=true) at ../libs/pbd/crossthread.posix.cc:123
#3  0x00007ffff6aaf01a in ARDOUR::Butler::thread_work (this=0x555559373730) at ../libs/ardour/butler.cc:172
#4  0x00007ffff6aaed9b in ARDOUR::Butler::_thread_work (arg=0x555559373730) at ../libs/ardour/butler.cc:153
#5  0x00007ffff41b3cf0 in fake_thread_start (arg=0x55555d55ac40) at ../libs/pbd/pthread_utils.cc:113
#6  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#7  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 37 (Thread 0x7fffc598e900 (LWP 5857)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, futex_word=0x55555d2d90c0) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  do_futex_wait (sem=sem@entry=0x55555d2d90c0, abstime=0x0) at sem_waitcommon.c:111
#2  0x00007fffef056988 in __new_sem_wait_slow (sem=0x55555d2d90c0, abstime=0x0) at sem_waitcommon.c:181
#3  0x00007ffff6bd23c4 in PBD::Semaphore::wait (this=0x55555d2d90c0) at ../libs/pbd/pbd/semutils.h:64
#4  0x00007ffff6bcfb60 in ARDOUR::Graph::run_one (this=0x55555d2d9010) at ../libs/ardour/graph.cc:426
#5  0x00007ffff6bd0018 in ARDOUR::Graph::helper_thread (this=0x55555d2d9010) at ../libs/ardour/graph.cc:470
#6  0x00007ffff6bd65c5 in boost::_mfi::mf0<void, ARDOUR::Graph>::operator() (this=0x7fffc598def8, p=0x55555d2d9010) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/mem_fn_template.hpp:49
#7  0x00007ffff6bd5d7a in boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> >::operator()<boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list0> (this=0x7fffc598df08, f=..., a=...) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:259
#8  0x00007ffff6bd51d7 in boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> > >::operator() (this=0x7fffc598def8) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:1294
#9  0x00007ffff6bd4a7b in boost::detail::function::void_function_obj_invoker0<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> > >, void>::invoke (function_obj_ptr=...) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/function/function_template.hpp:159
#10 0x0000555555bf23aa in boost::function0<void>::operator() (this=0x7fffc598def0) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/function/function_template.hpp:769
#11 0x00007fffcc45b055 in ARDOUR::AlsaAudioBackend::alsa_process_thread (arg=0x55555cf7cb30) at ../libs/backends/alsa/alsa_audiobackend.cc:1169
#12 0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#13 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 36 (Thread 0x7fffc5a12900 (LWP 5856)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, futex_word=0x55555d2d90e8) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  do_futex_wait (sem=sem@entry=0x55555d2d90e8, abstime=0x0) at sem_waitcommon.c:111
#2  0x00007fffef056988 in __new_sem_wait_slow (sem=0x55555d2d90e8, abstime=0x0) at sem_waitcommon.c:181
#3  0x00007ffff6bd23c4 in PBD::Semaphore::wait (this=0x55555d2d90e8) at ../libs/pbd/pbd/semutils.h:64
#4  0x00007ffff6bceeee in ARDOUR::Graph::reached_terminal_node (this=0x55555d2d9010) at ../libs/ardour/graph.cc:301
#5  0x00007ffff6bd6c9f in ARDOUR::GraphNode::finish (this=0x5555592ccc70, chain=0) at ../libs/ardour/graphnode.cc:74
#6  0x00007ffff6bd242e in ARDOUR::GraphNode::run (this=0x5555592ccc70, chain=0) at ../libs/ardour/ardour/graphnode.h:65
#7  0x00007ffff6bcfcce in ARDOUR::Graph::run_one (this=0x55555d2d9010) at ../libs/ardour/graph.cc:442
#8  0x00007ffff6bd03fa in ARDOUR::Graph::main_thread (this=0x55555d2d9010) at ../libs/ardour/graph.cc:523
#9  0x00007ffff6bd65c5 in boost::_mfi::mf0<void, ARDOUR::Graph>::operator() (this=0x7fffc5a11ef8, p=0x55555d2d9010) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/mem_fn_template.hpp:49
#10 0x00007ffff6bd5d7a in boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> >::operator()<boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list0> (this=0x7fffc5a11f08, f=..., a=...) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:259
#11 0x00007ffff6bd51d7 in boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> > >::operator() (this=0x7fffc5a11ef8) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:1294
#12 0x00007ffff6bd4a7b in boost::detail::function::void_function_obj_invoker0<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> > >, void>::invoke (function_obj_ptr=...) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/function/function_template.hpp:159
#13 0x0000555555bf23aa in boost::function0<void>::operator() (this=0x7fffc5a11ef0) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/function/function_template.hpp:769
#14 0x00007fffcc45b055 in ARDOUR::AlsaAudioBackend::alsa_process_thread (arg=0x55555d50ee90) at ../libs/backends/alsa/alsa_audiobackend.cc:1169
#15 0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#16 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 35 (Thread 0x7fffc5a1e900 (LWP 5855)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, futex_word=0x55555d66fc40) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  do_futex_wait (sem=sem@entry=0x55555d66fc40, abstime=0x0) at sem_waitcommon.c:111
#2  0x00007fffef056988 in __new_sem_wait_slow (sem=0x55555d66fc40, abstime=0x0) at sem_waitcommon.c:181
#3  0x00007ffff6bd23c4 in PBD::Semaphore::wait (this=0x55555d66fc40) at ../libs/pbd/pbd/semutils.h:64
#4  0x00007ffff7092d7d in ARDOUR::RTTaskList::run (this=0x55555d66fc10) at ../libs/ardour/rt_tasklist.cc:112
#5  0x00007ffff7092b6a in ARDOUR::RTTaskList::_thread_run (arg=0x55555d66fc10) at ../libs/ardour/rt_tasklist.cc:68
#6  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#7  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 34 (Thread 0x7fffc5a2a900 (LWP 5854)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, futex_word=0x55555d66fc40) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  do_futex_wait (sem=sem@entry=0x55555d66fc40, abstime=0x0) at sem_waitcommon.c:111
#2  0x00007fffef056988 in __new_sem_wait_slow (sem=0x55555d66fc40, abstime=0x0) at sem_waitcommon.c:181
#3  0x00007ffff6bd23c4 in PBD::Semaphore::wait (this=0x55555d66fc40) at ../libs/pbd/pbd/semutils.h:64
#4  0x00007ffff7092d7d in ARDOUR::RTTaskList::run (this=0x55555d66fc10) at ../libs/ardour/rt_tasklist.cc:112
#5  0x00007ffff7092b6a in ARDOUR::RTTaskList::_thread_run (arg=0x55555d66fc10) at ../libs/ardour/rt_tasklist.cc:68
#6  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#7  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Continued…

…continued

Thread 29 (Thread 0x7fffb9ffb700 (LWP 5828)):
#0  0x00007fffecc9c819 in __GI___poll (fds=0x7fffd40054f0, nfds=1, timeout=200) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fffcc45c204 in ARDOUR::AlsaAudioBackend::midi_device_thread (this=0x55555767af50) at ../libs/backends/alsa/alsa_audiobackend.cc:1366
#2  0x00007fffcc45c09c in ARDOUR::AlsaAudioBackend::_midi_device_thread (arg=0x55555767af50) at ../libs/backends/alsa/alsa_audiobackend.cc:1329
#3  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 28 (Thread 0x7fffc60ba900 (LWP 5827)):
#0  0x00007fffecc9c916 in __GI_ppoll (fds=0x5555574f9bdc, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007fffcc48b65c in Alsa_pcmi::pcm_wait (this=0x5555574f9b50) at ../libs/backends/alsa/zita-alsa-pcmi.cc:185
#2  0x00007fffcc45eaca in ARDOUR::AlsaAudioBackend::main_process_thread (this=0x55555767af50) at ../libs/backends/alsa/alsa_audiobackend.cc:1819
#3  0x00007fffcc458a9b in pthread_process (arg=0x55555767af50) at ../libs/backends/alsa/alsa_audiobackend.cc:775
#4  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 27 (Thread 0x7fffc60c6900 (LWP 5826)):
#0  0x00007fffecc9c819 in __GI___poll (fds=0x5555574c3930, nfds=1, timeout=100) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fffcc486394 in ARDOUR::AlsaRawMidiIn::main_process_thread (this=0x55555788a040) at ../libs/backends/alsa/alsa_rawmidi.cc:255
#2  0x00007fffcc483fc3 in pthread_process (arg=0x55555788a498) at ../libs/backends/alsa/alsa_midi.cc:68
#3  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 26 (Thread 0x7fffc60d2900 (LWP 5825)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x555557650f78) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x555557650f28, cond=0x555557650f50) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x555557650f50, mutex=0x555557650f28) at pthread_cond_wait.c:655
#3  0x00007fffcc485c77 in ARDOUR::AlsaRawMidiOut::main_process_thread (this=0x555557650f00) at ../libs/backends/alsa/alsa_rawmidi.cc:150
#4  0x00007fffcc483fc3 in pthread_process (arg=0x555557650f18) at ../libs/backends/alsa/alsa_midi.cc:68
#5  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 25 (Thread 0x7fffc60de900 (LWP 5824)):
#0  0x00007fffecc9c819 in __GI___poll (fds=0x5555577987a0, nfds=1, timeout=100) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fffcc486394 in ARDOUR::AlsaRawMidiIn::main_process_thread (this=0x555557889800) at ../libs/backends/alsa/alsa_rawmidi.cc:255
#2  0x00007fffcc483fc3 in pthread_process (arg=0x555557889c58) at ../libs/backends/alsa/alsa_midi.cc:68
#3  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 24 (Thread 0x7fffcc00a900 (LWP 5823)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x55555749d218) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x55555749d1c8, cond=0x55555749d1f0) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x55555749d1f0, mutex=0x55555749d1c8) at pthread_cond_wait.c:655
#3  0x00007fffcc485c77 in ARDOUR::AlsaRawMidiOut::main_process_thread (this=0x55555749d1a0) at ../libs/backends/alsa/alsa_rawmidi.cc:150
#4  0x00007fffcc483fc3 in pthread_process (arg=0x55555749d1b8) at ../libs/backends/alsa/alsa_midi.cc:68
#5  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 23 (Thread 0x7fffc58de700 (LWP 5822)):
#0  0x00007fffecc9f037 in __GI___select (nfds=1, readfds=0x7fffc58dbc00, writefds=0x0, exceptfds=0x0, timeout=0x7fffc58dbc80) at ../sysdeps/unix/sysv/linux/select.c:41
#1  0x00007ffff41c9e2a in PBD::SystemExec::output_interposer (this=0x555557ab8380) at ../libs/pbd/system_exec.cc:844
#2  0x00007ffff41c8f6a in interposer_thread (arg=0x555557ab8380) at ../libs/pbd/system_exec.cc:281
#3  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 12 (Thread 0x7fffc6ca5700 (LWP 5669)):
#0  0x00007fffecc9c819 in __GI___poll (fds=0x5555578bb5e0, nfds=2, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ffff2f40d66 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff2f40e7c in g_main_context_iteration () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#3  0x00007ffff2f40ec1 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#4  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#5  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7fffcd90d700 (LWP 5665)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff2f91e4c in g_cond_wait () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff6a39eb6 in ARDOUR::AudioEngine::do_devicelist_update (this=0x555557299b70) at ../libs/ardour/audioengine.cc:718
#3  0x00007ffff6a47f5b in boost::_mfi::mf0<void, ARDOUR::AudioEngine>::operator() (this=0x55555769e850, p=0x555557299b70) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/mem_fn_template.hpp:49
#4  0x00007ffff6a47902 in boost::_bi::list1<boost::_bi::value<ARDOUR::AudioEngine*> >::operator()<boost::_mfi::mf0<void, ARDOUR::AudioEngine>, boost::_bi::list0> (this=0x55555769e860, f=..., a=...) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:259
#5  0x00007ffff6a46f6f in boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AudioEngine>, boost::_bi::list1<boost::_bi::value<ARDOUR::AudioEngine*> > >::operator() (this=0x55555769e850) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:1294
#6  0x00007ffff6a46602 in sigc::adaptor_functor<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AudioEngine>, boost::_bi::list1<boost::_bi::value<ARDOUR::AudioEngine*> > > >::operator() (this=0x55555769e850) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:256
#7  0x00007ffff6a4567e in sigc::internal::slot_call0<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AudioEngine>, boost::_bi::list1<boost::_bi::value<ARDOUR::AudioEngine*> > >, void>::call_it (rep=0x55555769e820) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:103
#8  0x00007ffff34dac4d in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglibmm-2.4.so.1
#9  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#10 0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#11 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7fffcffff700 (LWP 5664)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff2f91e4c in g_cond_wait () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff6a39c77 in ARDOUR::AudioEngine::do_reset_backend (this=0x555557299b70) at ../libs/ardour/audioengine.cc:682
#3  0x00007ffff6a47f5b in boost::_mfi::mf0<void, ARDOUR::AudioEngine>::operator() (this=0x55555769e290, p=0x555557299b70) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/mem_fn_template.hpp:49
#4  0x00007ffff6a47902 in boost::_bi::list1<boost::_bi::value<ARDOUR::AudioEngine*> >::operator()<boost::_mfi::mf0<void, ARDOUR::AudioEngine>, boost::_bi::list0> (this=0x55555769e2a0, f=..., a=...) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:259
#5  0x00007ffff6a46f6f in boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AudioEngine>, boost::_bi::list1<boost::_bi::value<ARDOUR::AudioEngine*> > >::operator() (this=0x55555769e290) at /home/ardour/linux-x86_64-v5/gtk/inst/include/boost/bind/bind.hpp:1294
#6  0x00007ffff6a46602 in sigc::adaptor_functor<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AudioEngine>, boost::_bi::list1<boost::_bi::value<ARDOUR::AudioEngine*> > > >::operator() (this=0x55555769e290) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:256
#7  0x00007ffff6a4567e in sigc::internal::slot_call0<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::AudioEngine>, boost::_bi::list1<boost::_bi::value<ARDOUR::AudioEngine*> > >, void>::call_it (rep=0x55555769e260) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:103
#8  0x00007ffff34dac4d in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglibmm-2.4.so.1
#9  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#10 0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#11 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7fffe2bb9700 (LWP 5646)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff2f91e4c in g_cond_wait () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff69eda8c in ARDOUR::Analyser::work () at ../libs/ardour/analyser.cc:93
#3  0x00007ffff69ed878 in analyser_work () at ../libs/ardour/analyser.cc:58
#4  0x00005555564a33f5 in sigc::pointer_functor0<void>::operator() (this=0x555557279268) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/ptr_fun.h:77
#5  0x00005555564a0528 in sigc::adaptor_functor<sigc::pointer_functor0<void> >::operator() (this=0x555557279260) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:256
#6  0x000055555649c3b1 in sigc::internal::slot_call0<sigc::pointer_functor0<void>, void>::call_it (rep=0x555557279230) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:103
#7  0x00007ffff34dac4d in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglibmm-2.4.so.1
#8  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#9  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#10 0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7fffe33ba700 (LWP 5645)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff2f91e4c in g_cond_wait () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff71de3e2 in peak_thread_work () at ../libs/ardour/source_factory.cc:74
#3  0x00005555564a33f5 in sigc::pointer_functor0<void>::operator() (this=0x5555572791a8) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/ptr_fun.h:77
#4  0x00005555564a0528 in sigc::adaptor_functor<sigc::pointer_functor0<void> >::operator() (this=0x5555572791a0) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:256
#5  0x000055555649c3b1 in sigc::internal::slot_call0<sigc::pointer_functor0<void>, void>::call_it (rep=0x555557279170) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:103
#6  0x00007ffff34dac4d in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglibmm-2.4.so.1
#7  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#8  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#9  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7fffe3bbb700 (LWP 5644)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007ffff2f91e4c in g_cond_wait () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x00007ffff71de3e2 in peak_thread_work () at ../libs/ardour/source_factory.cc:74
#3  0x00005555564a33f5 in sigc::pointer_functor0<void>::operator() (this=0x555557265c28) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/ptr_fun.h:77
#4  0x00005555564a0528 in sigc::adaptor_functor<sigc::pointer_functor0<void> >::operator() (this=0x555557265c20) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:256
#5  0x000055555649c3b1 in sigc::internal::slot_call0<sigc::pointer_functor0<void>, void>::call_it (rep=0x555557265bf0) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:103
#6  0x00007ffff34dac4d in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglibmm-2.4.so.1
#7  0x00007ffff2f701e5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#8  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#9  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7fffe43bc700 (LWP 5643)):
#0  0x00007fffef057bf0 in __GI___nanosleep (requested_time=0x7fffe43bbbf0, remaining=0x7fffe43bbc00) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
#1  0x00007ffff2f71a38 in g_usleep () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#2  0x0000555556884acc in gui_event_loop (ptr=0x0) at ../gtk2_ardour/linux_vst_gui_support.cc:374
#3  0x00007fffef04dfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#4  0x00007fffecca74cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7fffe8962900 (LWP 5630)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x555559046720) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x555559046698, cond=0x5555590466f8) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x5555590466f8, mutex=0x555559046698) at pthread_cond_wait.c:655
#3  0x00007fffb822a144 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#4  0x00007fffb81c337d in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#5  0x00007fffb8255dc3 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#6  0x00007fffb825616b in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#7  0x00007fffb82f4870 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#8  0x00007fffb8258c6a in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#9  0x00007fffb81c3b83 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#10 0x00007fffb81c8ec8 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#11 0x00007fffb8199a4c in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#12 0x00007fffb8199dad in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#13 0x00007fffb8194d56 in ?? () from /usr/lib/lv2/linuxsampler.lv2/linuxsampler.so
#14 0x00007fffee796784 in lilv_state_restore () from /opt/Ardour-6.6.291-dbg/lib/liblilv-0.so.0
#15 0x00007ffff7247d5a in ARDOUR::LV2Plugin::init (this=0x55555ae7a7c0, c_plugin=0x5555586c9dd0, rate=48000) at ../libs/ardour/lv2_plugin.cc:950
#16 0x00007ffff7244d45 in ARDOUR::LV2Plugin::LV2Plugin (this=0x55555ae7a7c0, engine=..., session=..., c_plugin=0x5555586c9dd0, rate=48000) at ../libs/ardour/lv2_plugin.cc:405
#17 0x00007ffff7256cb8 in ARDOUR::LV2PluginInfo::load (this=0x5555595e6a70, session=...) at ../libs/ardour/lv2_plugin.cc:3521
#18 0x00007ffff70bad55 in ARDOUR::Session::load_and_connect_instruments (this=0x55555cfcbfe0, new_routes=Python Exception <class 'ValueError'> Cannot find type ARDOUR::RouteList::_Node: 
std::__cxx11::list, strict_io=true, instrument=..., pset=0x0, existing_outputs=...) at ../libs/ardour/session.cc:3275
#19 0x00007ffff70b4764 in ARDOUR::Session::new_midi_track (this=0x55555cfcbfe0, input=..., output=..., strict_io=true, instrument=..., pset=0x0, route_group=0x0, how_many=0, name_template="LinuxSampler", order=4294967295, mode=ARDOUR::Normal, input_auto_connect=true) at ../libs/ardour/session.cc:2482
#20 0x0000555555c0334d in ARDOUR_UI::session_add_midi_route (this=0x5555575e0910, disk=true, route_group=0x0, how_many=1, name_template="LinuxSampler", strict_io=true, instrument=..., pset=0x0, order=4294967295) at ../gtk2_ardour/ardour_ui.cc:1524
#21 0x0000555555c09b66 in ARDOUR_UI::add_route_dialog_response (this=0x5555575e0910, r=1) at ../gtk2_ardour/ardour_ui.cc:2802
#22 0x0000555555c3a6be in sigc::bound_mem_functor1<void, ARDOUR_UI, int>::operator() (this=0x55555acb3938, _A_a1=@0x7fffffffbffc: 1) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/mem_fun.h:1856
#23 0x0000555555c33177 in sigc::adaptor_functor<sigc::bound_mem_functor1<void, ARDOUR_UI, int> >::operator()<int const&> (this=0x55555acb3930, _A_arg1=@0x7fffffffbffc: 1) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:89
#24 0x0000555555c2a7a8 in sigc::internal::slot_call1<sigc::bound_mem_functor1<void, ARDOUR_UI, int>, void, int>::call_it (rep=0x55555acb3900, a_1=@0x7fffffffbffc: 1) at /home/ardour/linux-x86_64-v5/gtk/inst/include/sigc++-2.0/sigc++/functors/slot.h:137
#25 0x00007ffff06805f5 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgtkmm-2.4.so.1
#26 0x00007ffff324f945 in g_closure_invoke () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#27 0x00007ffff326101b in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#28 0x00007ffff326ac30 in g_signal_emit_valist () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#29 0x00007ffff326b082 in g_signal_emit () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#30 0x00007ffff248e0d4 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#31 0x00007ffff324fb74 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#32 0x00007ffff326a904 in g_signal_emit_valist () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#33 0x00007ffff326b082 in g_signal_emit () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#34 0x00007ffff244cd82 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#35 0x00007ffff324fb74 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#36 0x00007ffff326a904 in g_signal_emit_valist () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#37 0x00007ffff326b082 in g_signal_emit () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#38 0x00007ffff244af92 in gtk_button_released () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#39 0x00007ffff244b059 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#40 0x00007ffff2533cac in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#41 0x00007ffff324f945 in g_closure_invoke () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#42 0x00007ffff32615a0 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#43 0x00007ffff326a69b in g_signal_emit_valist () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#44 0x00007ffff326b082 in g_signal_emit () from /opt/Ardour-6.6.291-dbg/lib/libgobject-2.0.so.0
#45 0x00007ffff26b864c in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#46 0x00007ffff253229d in gtk_propagate_event () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#47 0x00007ffff2532723 in gtk_main_do_event () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#48 0x00007ffff214eb4c in ?? () from /opt/Ardour-6.6.291-dbg/lib/libgdk-x11-2.0.so.0
#49 0x00007ffff2f40b67 in g_main_context_dispatch () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#50 0x00007ffff2f40dd0 in ?? () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#51 0x00007ffff2f410f2 in g_main_loop_run () from /opt/Ardour-6.6.291-dbg/lib/libglib-2.0.so.0
#52 0x00007ffff25313e7 in gtk_main () from /opt/Ardour-6.6.291-dbg/lib/libgtk-x11-2.0.so.0
#53 0x00007ffff455e0e4 in Gtkmm2ext::UI::run (this=0x5555575e0910, old_receiver=...) at ../libs/gtkmm2ext/gtk_ui.cc:310
#54 0x00005555561d36bf in main (argc=1, argv=0x7fffffffd598) at ../gtk2_ardour/main.cc:410
(gdb)