I tried it also, but no help here either. I have almost the same
situation as Leslie, right down to running VirtualBox and an AMD CPU
running 64 bit.

The two differences are that my sound card is not listed as
"UNCLAIMED" in the lshw output, and my sound survived some time after
installing VirtualBox, in fact, it only recently died.

All I hear from the speakers now is a faint clicking. All is well on a
live CD though.