Version: 1.90 (using 4.1.1 (KDE 4.1.1), Kubuntu packages) Compiler: gcc OS: Linux (i686) release 2.6.24-19-generic .. at least by clicking on this speaker icon next to the volume bar .. which clicking on it right now does nothing. I don't think it is intuitive to right click on the volume bar and then presented by a menu of 100%, 80% ... 0% just to choose 0% to make a mute. Also providing a demute by pressing that button again will be optimal.
fixed in r860737