We were woken up with POLLOUT set -- however a subsequent snd_pcm_avail() returned 0 or another value < min_avail. Jun 09 14:31:33 elrond pulseaudio[11933]: Most likely this is a bug in the ALSA driver 'snd_usb_audio'. Please report this issue to the ALSA developers. Jun 09 14:31:33 elrond pulseaudio[11933]: ALSA woke us up to write new data to the device, but there was actually nothing to write.

[GitHub issues - opened]

alsa-project/alsa-lib issue #57 was opened from danieloppenlander:

I ran across an error in my journalctl on Ubuntu 20.04. It said to report a bug. Here is my alsa-info.sh output: http://alsa-project.org/db/?f=6b505aa5138f2a974037ab5c3a89e1605807df97

Issue URL     : https://github.com/alsa-project/alsa-lib/issues/57
Repository URL: https://github.com/alsa-project/alsa-lib