Reoccurred again on the next day after a cold reboot. Once it starts happening, pulseaudio doesn't need to be running to see the issue (acpi_listen plug/unplug events) so this is likely lower-level than pulseaudio.
Similar alsa-driver thread: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/874535
Reoccurred again on the next day after a cold reboot. Once it starts happening, pulseaudio doesn't need to be running to see the issue (acpi_listen plug/unplug events) so this is likely lower-level than pulseaudio.
Similar alsa-driver thread: https:/ /bugs.launchpad .net/ubuntu/ +source/ alsa-driver/ +bug/874535