Ardour 6.7 cannot connect to JACK anymore

I just installed Ardour 6.7 and cannot connect to my JACK. Latest MIxbus and Reaper can.

I am in groups audio and realtime. I can use realtime jackd with Guitarix and Mixbus.

My Log:

Here are the errors associated with this failed session:
Log Messages:
ERROR: JACK: Cannot use real-time scheduling (RR/5) (1: Operation not permitted)
ERROR: JACK: JackClient::AcquireSelfRealTime error
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)
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)
WARNING: Unsupported required LV2 feature: ‘LV2 Buf Size’ in ‘KlangFalter’.
WARNING: Unsupported required LV2 feature: ‘LV2 Buf Size’ in ‘Vex’.
INFO: harvid version: 803
INFO: Loading menus from /opt/Ardour-6.7.0/etc/ardour.menus
ERROR: JACK: Cannot create thread res = 1

Is this associated with Ardour 6.7?

I use Ardour with JACK all day every day. There has been no change in Ardour’s JACK support.

On the other, your system JACK config is clearly broken:

ERROR: JACK: Cannot use real-time scheduling (RR/5) (1: Operation not permitted)
ERROR: JACK: JackClient::AcquireSelfRealTime error

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I’ve ran into this before with JACK, but specifically only when I also have pipewire installed and am not using pipewire-jack. Can you give us some more details about what system and configuration you are running?

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Ardour can only use JACK if jack runs with realtime permissions.

On debian based systems, run

sudo dpkg-reconfigure -p high jackd2

and allow realtime process priority. Then re-login and configure jackd to use rt-permissions (it’s usually enabled by default if available).

Generic instructions for other distros can be found in the jack FAQ: How do I configure my linux system to allow JACK to use realtime scheduling? | JACK Audio Connection Kit

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Yes, I fixed it. It was the audio group conf. :no_mouth:

It’s a Manjaro. I already fixed it, but thanks for your help anyways. :slight_smile:

I feel a little bit dumb now. I checked the audio.conf – somehow it was not there, but in a different folder.
I really dont know, how this happened. And, how it worked all the time before installing A6.7. o.O