Unfortunately I wouldn't have much more to add to what hylke said already. I am a newbie also, my knowledge/experience aren't that extended yet.
I could post you what my Alsamixer shows, but I know you are using USB headphones, I don't know if you can change anything from there...
Actually, try to type in panel
- Code: Select all
and check if the headset is recognised, because you can tamper alsamixer ad infinitum
but if the computer doesn't see the USB device you won't obtain anything.
I hope this helps, I'm your supporter even if I don't have a clue either, more or less