I've searched in this forum (and in many many others) but still I've not found a solution. The sound through headphone's output is very very low.
I've recently moved from Ubuntu 11.04 to Linux Mint Debian Edition (MATE).
I've had the same problem when I was using Ubuntu (from 10.04 on) and the solution was to edit the /etc/modprobe.d/alsa-base.conf file, adding the lines:
options snd-hda-intel model=toshiba
options snd-card-0 index=0 model=toshiba
since my laptop is a Toshiba Satellite A200.
Now this solution seems not working anymore; I've tried also "model=3stack" and "model=basic" with no luck.
Audio from laptop speakers works very well, but there are few odd things that had never happened in my experience:
1. when audio settings is opened, in the hardware section I see the internal audio option but I can't choose headphone in the scroll menu below because this option is missing, while in Ubuntu there it was
2. there is a 2.1 speakers system connected to the headphone's output; when the volume is set to the maximum, I hear a really low sound (this happened also with Ubuntu, before editing alsa-base.conf file)
3. when I open alsamixer from the terminal, it seems that the speaker/PCM controls work in a synchronous fashion wrt the master one (if I move one of the two, master moves too) while if I move headphone control, master does not move (don't know if this is relevant)
Thanks to all for your support.