88fingerslukee,
Which display driver version are you using? Providing an nvidia-bug-report would help.
Can you please try each of the following:
speaker-test -c 2 -r 48000 hw:0,3
speaker-test -c 2 -r 48000 hw:0,7
speaker-test -c 2 -r 48000 hw:0,8
speaker-test -c 2 -r 48000 hw:0,9
Do any of those work?
If so, please see my post #7 here:
http://www.nvnews.net/vbulletin/showthread.php?t=154755
In particular, problem (c) in that post.