I'm at a loss.

I'm using Ubuntu 12.04 LTS x64, and have not installed any audio mixers, front ends, etc, beyond what shipped with 12.04. I've tried to keep the system clean as it makes it easier to troubleshoot.

ALSA identifies this card correctly, but it has no controls for the subwoofer in alsamixer. Controls for Surround and Center are there and they all work fine. In the Pulse mixer that ships with 12.04 (the one you can access through the volume control on the taskbar) I can test sound channels and they all work, except the subwoofer, which just gives a low frequency noise I can barely hear.

Does anyone have any tips for figuring this out? Between ALSA and Pulse I'm not sure exactly where the problem lies, but I'm leaning towards ALSA since it doesn't even have an entry for a subwoofer channel, but with past problems with Pulse I really am not sure.

Trying to get this setup for Steam. Thank you for your time, and any help you can provide.