Comment 8 for bug 1291862

Ara,

 I install the 14.04, and find there are use 'unity-control-center sound' for change sound setting.

 First run 'unity-control-center sound', and insert the microphone in front panel, the input bar could be adjusted. But when I plug out the microphone, the input bar is still enabled, and you can change the input level, in next time when you insert microphone again, you will find the input level was the latest change which is we changed without inserting microphone.

 And I found soucecode is similar with gnome-control-center sound-nua, I'll try to made a patch for trusty.