When I launch Jitsi from an icon in Unity's Launcher, I do not get any
sound. When I launch Jitsi manually from the shell, I get proper sound.
The symptom occurs only when launching from the Launcher and can also
be seen from Tools->Options->Audio System where it says "audiosilence"
This has been consistent since October or earlier and is quite
consistent. It is present even in Jitsi 2.9.5442-1
$ apt-cache policy jitsi
Looking around, I see two .desktop files which seem not to be used:
The problem looks like it might be coming from
~/.local/share/applications/jitsi.desktop, which is the .desktop file
that Unity seems to decide to use when selecting "Lock to launcher" In
Editing that .desktop file and replacing that Exec with the following
seems to prevent restriction of sound options to audio silence:
Deleting /.local/share/applications/jitsi.desktop makes the default
audiosilence problem come back.