Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason. Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to? In some cases on a remote system you can't easily reinstall without physical or KVM access.
So in this case you add a second physical or disk or already ha........
ProCurve J4903A Switch 2824
Software revision I.10.77
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What this really refers to is gnome-volume-control-applet which is what controls the volume in the panel/indicator applet.
In Ubuntu 10.04 it is just the applet mentioned above, run that from the command line and it will start.
I lost mine when I removed pulseaudio trying to fix audio issues with Flash and Opera. It also removes the gnome-volume-control-applet from starting. *Ialso note........