Found it:
https://bugs.launchpad.net/ubuntu/+source/gnome-settings-daemon/+bug/1248368
Had to downgrade gnome-settings-daemon, and volume keys worked again.
Volume up, volume down, and mute are all recognized by the system. It seems
like the commands themselves no longer work. Other media commands like
play/pause and stop work just fine. I tried changing the keyboard shortcuts
for the volume commands, but still no luck.
Just recently I noticed my volume shortcut keys stopped working. I thought it
was an isolated case, but the same thing happened to my other laptop. It most
likely had something to do with the most recent upgrade. Can anyone else
confirm?
If you're on the trisquel-mini version, then the problem is with openbox (the
window manager) and no workaround for a faulty alsa.
Try these commands in a terminal:
amixer -qc0 set Master toggle;amixer -qc0 set Headphone unmute;amixer -qc0
set Speaker unmute
If your sounds back on then open
