I can confirm that if I stop and restart pulse audio as told in https://wiki.ubuntu.com/PulseAudio/Log, the "sound preference" entry will work, and the bug comes back. Deleting the .pulse directory, again, makes the sound working again.
If someone direct me, I can help testing thing. Will a PulseAudio/Log be useful?
I can confirm that if I stop and restart pulse audio as told in https:/ /wiki.ubuntu. com/PulseAudio/ Log, the "sound preference" entry will work, and the bug comes back. Deleting the .pulse directory, again, makes the sound working again.
If someone direct me, I can help testing thing. Will a PulseAudio/Log be useful?