Sound automatically switch from USB Speaker to HeadSet

[GitHub issues - opened]

alsa-project/alsa-lib issue #215 was opened from modulusmath:

Ubuntu 21.10 / Codename: impish

Running LXDE if it matters

I watch youtube listening on my external usb speakers and sounds plays just fine.

All of a sudden they go silent and sound is played on the plugged in headset (Plantronics, Inc. DA40 Adapter) without my intervention...Even if I unplug the headset it will switch over to the 'default usb audio analog stereo'. 


I do see some logs via journalctl near the time of the switch:

Mar 01 10:04:57 wilddog pulseaudio[1678]: ALSA woke us up to write new data to the device, but there was actually nothing to write.
Mar 01 10:04:57 wilddog pulseaudio[1678]: Most likely this is a bug in the ALSA driver 'snd_usb_audio'. Please report this issue to the ALSA developers.
Mar 01 10:04:57 wilddog pulseaudio[1678]: We were woken up with POLLOUT set -- however a subsequent snd_pcm_avail() returned 0 or another value < min_avail.

This is a pretty fresh install.

How can I keep it stable on the external speakers?

Here's my also info: http://alsa-project.org/db/?f=3589356420b912e19608eaee1960f19b3f0a4e22

Issue URL     : https://github.com/alsa-project/alsa-lib/issues/215
Repository URL: https://github.com/alsa-project/alsa-lib