On further investigation. Looks similar to Bug #1026331 (duplicate of #878986). Which, according to the comments on the latter is a Pulseaudio issue.
Fixed (or rather triaged) by using amixer -D pulse set Master toggle (which worked for me) or using pactl set-sink-mute <default_sink_name> 0 (which wouldn't recognise the sink name) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1313813 Title: amixer 'mute toggle shortcut' problem (can mute but not unmute) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-utils/+bug/1313813/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
