Comment # 1 on bug 916048 from Takashi Iwai

Could you check whether it's a problem of PulseAudio or the driver itself?
For example,
- Go to runlevel 3 and login
- Make sure that no pulseaudio process is running
- Unmute and adjust the level of both "Headphone" and "Speaker" via "alsamixer
-c0"
- Play something via "aplay -Dplughw something.wav"
- Plug or unplug the headphone, test playing.  Check whether pulseaudio is
really not running meanwhile.

If the test above passes, the problem is in PulseAudio.  If the above fails,
it's a driver issue.