"PulseAudio was supposed to cure desktop audio in Linux. It
promised useful features like device routing and individual volume
controls. It may well do these things; in my experience it has been
frustrating, opaque, and unreliable.
"Some have claimed that Ubuntu's implementation is flawed; I
haven't looked at other distros yet, so I don't know. On my Ubuntu
10.04 system there are five separate sound control panels lurking
in various locations, four PulseAudio and one Gnome:
1. System > Preferences > Sound is the Gnome sound control
2. Which looks a lot like System > Preferences > PulseAudio
3. Then there is Applications > Sound and Video > PulseAudio
Device Chooser (padevchooser)"