Choppy sound (recording and playback)

Hello everyone,

I’m having a very strange problem here. I get choppy sound on record or playback, and this is new on my system !
Before we start, let me give you the specifics of my system :

  • Using Jack audio server
  • Using PlanetCCRMA RT kernel
  • Never experience Jack XRuns !

The symptoms look like it’s a Jack backend problem. I tried to change the latency, the sampling format of the files, nothing is good. I’m still having this choppy sound.

The last recording I made on this machine was in the exact same conditions, 10 days ago, and the sound is perfect !
The only thing that changed is a system update.

I’m running Fedora 19, so here is the YUM log. Maybe that could tell something :

Dec 20 11:53:40 Updated: libgcc-4.8.2-7.fc19.x86_64
Dec 20 11:53:40 Updated: libstdc++-4.8.2-7.fc19.x86_64
Dec 20 11:53:41 Updated: satyr-0.12-1.fc19.x86_64
Dec 20 11:53:42 Updated: 1:libreoffice-ure-4.1.3.2-12.fc19.x86_64
Dec 20 11:53:42 Updated: colord-libs-1.0.5-2.fc19.x86_64
Dec 20 11:53:42 Updated: libquadmath-4.8.2-7.fc19.x86_64
Dec 20 11:53:43 Updated: gnutls-3.1.17-2.fc19.x86_64
Dec 20 11:53:43 Updated: gnutls-dane-3.1.17-2.fc19.x86_64
Dec 20 11:53:43 Updated: libgfortran-4.8.2-7.fc19.x86_64
Dec 20 11:53:44 Updated: colord-1.0.5-2.fc19.x86_64
Dec 20 11:53:46 Updated: libstdc++-devel-4.8.2-7.fc19.x86_64
Dec 20 11:53:49 Updated: 1:qt-4.8.5-11.fc19.x86_64
Dec 20 11:53:49 Updated: libreport-filesystem-2.1.10-1.fc19.x86_64
Dec 20 11:53:49 Updated: libreport-python-2.1.10-1.fc19.x86_64
Dec 20 11:53:49 Updated: libreport-2.1.10-1.fc19.x86_64
Dec 20 11:53:49 Updated: abrt-libs-2.1.10-1.fc19.x86_64
Dec 20 11:53:49 Updated: libreport-web-2.1.10-1.fc19.x86_64
Dec 20 11:53:49 Updated: libreport-plugin-ureport-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: abrt-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: abrt-python-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: abrt-addon-python-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: abrt-addon-xorg-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: abrt-plugin-bodhi-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: abrt-dbus-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: libreport-plugin-bugzilla-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: libreport-plugin-kerneloops-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: abrt-addon-kerneloops-2.1.10-1.fc19.x86_64
Dec 20 11:53:50 Updated: abrt-addon-vmcore-2.1.10-1.fc19.x86_64
Dec 20 11:53:51 Updated: abrt-addon-pstoreoops-2.1.10-1.fc19.x86_64
Dec 20 11:53:51 Updated: libreport-plugin-reportuploader-2.1.10-1.fc19.x86_64
Dec 20 11:53:51 Updated: libreport-gtk-2.1.10-1.fc19.x86_64
Dec 20 11:53:51 Updated: abrt-gui-libs-2.1.10-1.fc19.x86_64
Dec 20 11:53:51 Updated: abrt-gui-2.1.10-1.fc19.x86_64
Dec 20 11:53:51 Updated: libreport-plugin-logger-2.1.10-1.fc19.x86_64
Dec 20 11:53:51 Updated: libreport-fedora-2.1.10-1.fc19.x86_64
Dec 20 11:53:51 Updated: 1:autocorr-fr-4.1.3.2-12.fc19.noarch
Dec 20 11:53:52 Updated: 2:tar-1.26-28.fc19.x86_64
Dec 20 11:53:52 Updated: abrt-retrace-client-2.1.10-1.fc19.x86_64
Dec 20 11:53:52 Updated: abrt-addon-ccpp-2.1.10-1.fc19.x86_64
Dec 20 11:53:53 Updated: argyllcms-1.6.2-1.fc19.x86_64
Dec 20 11:53:53 Updated: pciutils-libs-3.2.1-1.fc19.x86_64
Dec 20 11:53:54 Updated: 1:autocorr-en-4.1.3.2-12.fc19.noarch
Dec 20 11:53:54 Updated: libgomp-4.8.2-7.fc19.x86_64
Dec 20 11:53:57 Updated: cpp-4.8.2-7.fc19.x86_64
Dec 20 11:54:03 Updated: gcc-4.8.2-7.fc19.x86_64
Dec 20 11:54:03 Updated: 1:libreoffice-opensymbol-fonts-4.1.3.2-12.fc19.noarch
Dec 20 11:54:47 Updated: 1:libreoffice-core-4.1.3.2-12.fc19.x86_64
Dec 20 11:54:50 Updated: 1:libreoffice-writer-4.1.3.2-12.fc19.x86_64
Dec 20 11:54:51 Updated: 1:libreoffice-pyuno-4.1.3.2-12.fc19.x86_64
Dec 20 11:54:51 Updated: 1:libreoffice-graphicfilter-4.1.3.2-12.fc19.x86_64
Dec 20 11:54:52 Updated: 1:libreoffice-draw-4.1.3.2-12.fc19.x86_64
Dec 20 11:54:52 Updated: 1:libreoffice-pdfimport-4.1.3.2-12.fc19.x86_64
Dec 20 11:54:52 Updated: 1:libreoffice-emailmerge-4.1.3.2-12.fc19.x86_64
Dec 20 11:54:56 Updated: 1:libreoffice-calc-4.1.3.2-12.fc19.x86_64
Dec 20 11:54:57 Updated: 1:libreoffice-impress-4.1.3.2-12.fc19.x86_64
Dec 20 11:55:02 Updated: 1:libreoffice-langpack-fr-4.1.3.2-12.fc19.x86_64
Dec 20 11:55:03 Updated: 1:libreoffice-math-4.1.3.2-12.fc19.x86_64
Dec 20 11:55:06 Updated: gcc-c++-4.8.2-7.fc19.x86_64
Dec 20 11:55:06 Updated: pciutils-3.2.1-1.fc19.x86_64
Dec 20 11:55:09 Updated: gnome-color-manager-3.8.3-2.fc19.x86_64
Dec 20 11:55:09 Updated: abrt-desktop-2.1.10-1.fc19.x86_64
Dec 20 11:55:15 Updated: 1:qt-x11-4.8.5-11.fc19.x86_64
Dec 20 11:55:18 Updated: 1:numpy-1.7.1-7.fc19.x86_64
Dec 20 11:55:18 Updated: gnutls-utils-3.1.17-2.fc19.x86_64
Dec 20 11:55:22 Updated: llvm-libs-3.3-3.fc19.x86_64
Dec 20 11:55:23 Updated: highlight-3.16.1-1.fc19.x86_64
Dec 20 11:55:24 Updated: yum-3.4.3-122.fc19.noarch
Dec 20 11:55:24 Updated: libbluray-0.4.0-2.fc19.x86_64
Dec 20 11:55:24 Updated: SDL-1.2.15-12.fc19.x86_64
Dec 20 11:55:25 Updated: 1:wpa_supplicant-2.0-8.fc19.x86_64
Dec 20 11:55:25 Updated: libgcc-4.8.2-7.fc19.i686
Dec 20 11:55:25 Updated: libstdc++-4.8.2-7.fc19.i686
Dec 22 20:45:38 Updated: glibc-2.17-20.fc19.x86_64
Dec 22 20:45:57 Updated: glibc-common-2.17-20.fc19.x86_64
Dec 22 20:45:59 Updated: 1:libreoffice-ure-4.1.4.2-1.fc19.x86_64
Dec 22 20:45:59 Updated: cryptsetup-libs-1.6.3-1.fc19.x86_64
Dec 22 20:46:01 Updated: kernel-headers-3.12.5-200.fc19.x86_64
Dec 22 20:46:02 Updated: glibc-headers-2.17-20.fc19.x86_64
Dec 22 20:46:02 Updated: 1:autocorr-en-4.1.4.2-1.fc19.noarch
Dec 22 20:46:02 Updated: 1:libreoffice-opensymbol-fonts-4.1.4.2-1.fc19.noarch
Dec 22 20:46:47 Updated: 1:libreoffice-core-4.1.4.2-1.fc19.x86_64
Dec 22 20:46:51 Updated: 1:libreoffice-writer-4.1.4.2-1.fc19.x86_64
Dec 22 20:46:52 Updated: 1:libreoffice-pyuno-4.1.4.2-1.fc19.x86_64
Dec 22 20:46:52 Updated: 1:libreoffice-graphicfilter-4.1.4.2-1.fc19.x86_64
Dec 22 20:46:53 Updated: 1:libreoffice-draw-4.1.4.2-1.fc19.x86_64
Dec 22 20:46:53 Updated: 1:libreoffice-pdfimport-4.1.4.2-1.fc19.x86_64
Dec 22 20:46:53 Updated: 1:autocorr-fr-4.1.4.2-1.fc19.noarch
Dec 22 20:46:58 Updated: 1:libreoffice-langpack-fr-4.1.4.2-1.fc19.x86_64
Dec 22 20:46:58 Updated: 1:libreoffice-emailmerge-4.1.4.2-1.fc19.x86_64
Dec 22 20:47:02 Updated: 1:libreoffice-calc-4.1.4.2-1.fc19.x86_64
Dec 22 20:47:03 Updated: 1:libreoffice-impress-4.1.4.2-1.fc19.x86_64
Dec 22 20:47:04 Updated: 1:libreoffice-math-4.1.4.2-1.fc19.x86_64
Dec 22 20:47:05 Updated: glibc-devel-2.17-20.fc19.x86_64
Dec 22 20:47:05 Updated: cryptsetup-1.6.3-1.fc19.x86_64
Dec 22 20:47:06 Updated: sudo-1.8.6p7-2.fc19.x86_64
Dec 22 20:47:06 Updated: icedtea-web-1.4.1-1.fc19.x86_64
Dec 22 20:47:06 Updated: netpbm-10.61.02-7.fc19.x86_64
Dec 22 20:47:06 Updated: xorg-x11-drv-qxl-0.1.1-3.fc19.x86_64
Dec 22 20:47:10 Updated: ca-certificates-2013.1.95-1.fc19.noarch
Dec 22 20:47:29 Installed: kernel-3.12.5-200.fc19.x86_64
Dec 22 20:47:31 Installed: kernel-modules-extra-3.12.5-200.fc19.x86_64
Dec 22 20:47:34 Updated: glibc-2.17-20.fc19.i686
Dec 23 12:12:26 Updated: 1:openssl-libs-1.0.1e-36.fc19.x86_64
Dec 23 12:12:26 Updated: 1:openssl-1.0.1e-36.fc19.x86_64
Dec 23 12:12:28 Updated: 1:openssl-devel-1.0.1e-36.fc19.x86_64
Dec 23 12:12:28 Updated: iftop-1.0-0.6.pre2.fc19.x86_64
Dec 23 12:12:28 Updated: libisofs-1.3.4-1.fc19.x86_64
Dec 23 12:12:29 Updated: libburn-1.3.4-1.fc19.x86_64
Dec 23 12:12:30 Updated: libreswan-3.7-1.fc19.x86_64
Dec 23 21:03:06 Installed: opus-devel-1.1-1.fc19.x86_64

I really don’t know where to look. If anyone has an idea, it would be really welcome.

Thanks in advance.

Hoggins!

I just installed the lastest version from source, and the problem still occurs.
I wiped out the previous ardour configuration, just to see if anything I had previously changed could have affected its normal behaviour. No effect.

But I noticed something quite strange : even when idle (no playback, no recording), the transport timestamp jumps to another value for a few milliseconds, and returns back to its current value.

Could these curious time jumps be causing my troubles ? Am I near a black hole occasionnaly warping time around me ?

Interesting : when I enable monitoring, I also get these glitches in audio, in real time. That’s annoying, and that proves the responsibility of Ardour here, but I cannot find how it ended like that.

What a shame. I switched to Audacity, using PortAudio to connect to Jack (PortAudio is not known to be the most stable connector to Jack), and it works like a charm. No audible audio dropouts.
I feel sad because there is no comparison between Ardour and Audacity, in terms of performance and ease of use. If I could, I would stick to Ardour.
But hey. If it refuses to perform ok, I’ll let it down.

Did you try to boot with the old kernel?

Yes, of course. I tried with different versions of different kernel types. RT and “normal”. No luck.

hey! i had this same issue on Pop OS 22.04 (which is Ubuntu 22.04 give or take wayland) on my 6th gen Thinkpad X1 Carbon. (listed because i think this might be a hw issue)

I resolved it by unplugging all audio equipment, force-killing ardour and restarting jack (or you could probably just reboot), starting ardour, and THEN finally plugging everything back in. It seems that when jack starts and the devices are already plugged in something goes weird.

hope this helps! ^^