Affected by this same bug.
Workaround described on https://bugs.launchpad.net/ubuntu/+source/linux-oem-osp1/+bug/1864061/comments/9 did not do the trick either.
The only solution that worked (but not always, sometimes it just duplicates "Dummy output") was `pulseaudio -k && sudo alsa force-reload`.
Affected by this same bug.
Workaround described on https:/ /bugs.launchpad .net/ubuntu/ +source/ linux-oem- osp1/+bug/ 1864061/ comments/ 9 did not do the trick either.
The only solution that worked (but not always, sometimes it just duplicates "Dummy output") was `pulseaudio -k && sudo alsa force-reload`.