amixer 'mute toggle shortcut' problem (can mute but not unmute)

[André Campos Rodovalho]

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)

[Jeffrey Tees (jeff-tees)]

Also affects Ubuntu 14.04 Vanilla (running standalone Xmonad Window Manager, not Unity Desktop on Acer Aspire One D260).

amixer -q sset Master toggle (or Master,0) also mutes Headphone and Speaker but does not unmute Headphone and Speaker when run again to unmute.

Problem persists whether system plugged into speakers through headphone jack or not.

Work-around also fixes problem for Xmonad (and also Herbstluftwm and other window managers) on vanilla Ubuntu.

I have no additional languages installed (Native English speaker) , but ibus is managing keyboard (as default in 14.04).

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Jeffrey Tees (jeff-tees)]

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)