try this command from the terminal:
answered 25 Jun '10, 12:01
If you can't get things going at the GUI level, all of the lower-level information you'll need to sort out the problem is in /proc/asound.
It will show what hardware is recognized (cards), what kernel modules are loaded (modules), what devices are tied to what hardware (devices along with pcm) as well as a host of other details.
answered 06 Aug '10, 15:27