I'm on a dell studio 1749 x64. internal speakers work just fine. I have three jacks near the front,2 are for audio and 1 for input.
When I plug my speakers into the audio (headphone) jack(s) I get nothing.
I've tried the alsamixer, switching the sound card, making sure nothing was muted, etc. With alsamixer open, I've tried to force it to recognize by unplugging and replugging, and it then mutes the channel in alsamixer which is easy enough to change but it doesn't fix anything. I've also tried adding lines to alsa-base.conf, again nothing.
The added lines to .conf are as follows:
options snd-hda-intel model=dell, options snd-hda-intel model=STAC92xx, options snd-hda-intel model=dell-m81, options snd-hda-intel model=gateway,
I know I only need 1 line but I'm not sure of my model so I left them all in there for extra measure. I thought they could be conflicting so I added (and rebooted) 1 at a time. No luck.
I'm on a fresh install of 12.04 LTS and I'll pastebin a log of any information needed.