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 Touch seeded packages, which is subscribed to alsa-utils in Ubuntu. https://bugs.launchpad.net/bugs/1313813 Title: amixer 'mute toggle shortcut' problem (can mute but not unmute) Status in “alsa-utils” package in Ubuntu: Confirmed Bug description: Openbox shortcut configuration file on ~/.config/openbox/lubuntu- rc.xml triggers to the following command to be executed: $ amixer -q sset Master toggle This problem is language related/dependent. This works fine on a pure english Lubuntu installation (toggle behavior). I installed Portuguese language package, on this very same machine, and now shortcut can mute, but I need to use the volume control on "tray" to unmute! I can solve the issue by running this command: $ amixer -q sset Master toggle && amixer -q sset Speaker unmute && amixer -q sset Headphone unmute A good workaround is edit ~/.config/openbox/lubuntu-rc.xml and set/reset this config.: <keybind key="XF86AudioMute"> <action name="Execute"> <command>amixer -q sset Master toggle</command> </action> <action name="Execute"> <command>amixer -q sset Speaker unmute</command> </action> <action name="Execute"> <command>amixer -q sset Headphone unmute</command> </action> </keybind> ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: alsa-utils 1.0.27.2-1ubuntu2 ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9 Uname: Linux 3.13.0-24-generic x86_64 ApportVersion: 2.14.1-0ubuntu3 Architecture: amd64 CurrentDesktop: LXDE Date: Mon Apr 28 13:19:33 2014 InstallationDate: Installed on 2014-04-27 (1 days ago) InstallationMedia: Lubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.2) SourcePackage: alsa-utils UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-utils/+bug/1313813/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
