I had a similar problem that may be related. I first noticed that my sound was not working
after a pulseaudio update. There was a partial workaround to get sound working again here:
where alsamixer -Dhw revealed that the PCM volume was at zero, and turning it up restored
sound operation. I still have the problem that my system hangs during shutdown while it is
shutting down ALSA. I think that may be because pulseaudio -k does not work, and pulseaudio
is an ALSA client.
I had a similar problem that may be related. I first noticed that my sound was not working
after a pulseaudio update. There was a partial workaround to get sound working again here:
https:/ /bugs.launchpad .net/ubuntu/ +source/ linux/+ bug/288861
where alsamixer -Dhw revealed that the PCM volume was at zero, and turning it up restored
sound operation. I still have the problem that my system hangs during shutdown while it is
shutting down ALSA. I think that may be because pulseaudio -k does not work, and pulseaudio
is an ALSA client.
Here is a list of similar bugs:
#288861
#288652
#288093
#288039
#286966
#286430
#285965