Comment # 1 on bug 913686 from Takashi Iwai

Could you try without PulseAudio if you're using it?  For example, try to login
on Linux console without GUI, adjust the mixer volume via "alsamixer -c0" (or
-c1), and play like "aplay -Dsysdefault somefile.wav".

With the above, does the problem still happen?  If yes, please give
alsa-info.sh outputs at each state (dock / headphone plugged/unplugged).  Run
the script with --no-upload option, and attach the outputs to Bugzilla (don't
paste).