I've been looking for a solution for days, and can't find one. Now I really can't put any use to my cosmic edition... DxDiag attached.
Nothing seems wrong from the dxdiag, assuming you're running a 64 bit OS. Vista doesn't seem to show which version it is, though you're showing over 4 gigs of RAM and what looks to be x64 video drivers. Only thing I can offer to try is see if there are updates to your sound and possibly video drivers. Some have reported updating their sound drivers fixing issues for them. Also see this sticky post: viewtopic.php?f=71&t=47593 If that fails please upload a recent .dmp file.
Check these two of my posts: viewtopic.php?p=740936#p740936 viewtopic.php?p=741744#p741744 I clearly explain it here.
