Created attachment 128100 [details]
Originally reported on Gnome's bugzilla: https://bugzilla.gnome.org/show_bug.cgi?id=772980
How to reproduce:
Run pulseaudio in gdb and stop pulseaudio execution so that the pulseaudio process stays alive, but doesn't respond to any client requests. All client operations get a timeout after 30 seconds in this state.
Open gnome-terminal and press tab. Normally that should cause a short blip sound, but since pulseaudio is stopped, no sound is expected in this case.
The problem is that gnome-shell hangs for 30 seconds. The backtrace (attached) shows that libmutter is playing the blip sound using ca_context_play_full(). ca_context_play_full() is supposed to be asynchronous, but it nevertheless blocks in this situation.
It's very annoying when this happens while debugging pulseaudio.
libcanberra version: 0.30-3 (Debian testing)