#1153340 linux: snd-usb-audio playback stalls on Axe-Fx III since 6.12.114 (needs upstream 70b4db7d2581)

Package:
src:linux
Source:
src:linux
Submitter:
Laszlo Burian
Date:
2026-11-07 13:09:02 UTC
Severity:
normal
#1153340#5
Date:
2026-11-07 13:07:07 UTC
From:
To:
Since upgrading from linux-image-6.12.113+deb13-amd64 (6.12.113-1) to
linux-image-6.12.115+deb13.1-amd64 (6.12.115-2), USB audio playback to a
Fractal Audio Axe-Fx III (2466:8010) stalls. The PCM is RUNNING with
hw_ptr stuck at 0 and PipeWire clients hang. Booting 6.12.113 again
makes it work.

6.12.114 brought in upstream ef5749ef8b30 ("ALSA: usb-audio: Prevent
excessive number of frames"). Upstream fixed a regression it caused
(bugzilla.kernel.org #220997) with:

  70b4db7d2581 ("ALSA: usb-audio: Use the right limit for PCM OOB check")

That fix is not in 6.12.y stable (checked through 6.12.116). It is a
one-line change to sound/usb/pcm.c. Please consider adding it to the
Debian kernel. I have also asked stable@vger.kernel.org to backport it.

Thanks,
Laszlo