hmmm, try this to see what we need to do.
Just to make sure that it isnt a wierd configuration issue with gnome-cd, is try noatun (RH menu -> Extras -> Sound & Video -> Noatun). Chances are that that wont work, but if it does, we know that its a bad setting with gnome-cd.
If neither work (as expected), try doing the following commands as root:
chmod 666 /dev/dsp*
chmod 666 /dev/mixer
That allows all users (as in not just root) access to all of the sound channels. I do not recall if I needed to do this upon installing RH 8 or not. If it happened before yesterday, I pobably wont remember ;D