I have an Aspire 3003LCi notebook with Windows XP.  My DVD audio quit
working the other day.  It may have something to do with my trying to clear
space on my drive; I may have gotten overzealous in deleting things.  In
fact, in retrospect, I think I deleted something related to Realtek AC97,
which of course, I know now, is my audio device, or something like that.  I
think the measures I have tried include reinstalling the device, as well as
its driver, and something involving downloading something from the system CD
(not the set of 3 recovery CDs, which, it is said, destroy all data on the
drives, which, of course, I really don't want to do.

I did try system restore, with no luck.

The drive is a DVD/CD-ROM-RW.  Everything else works perfectly: system
sounds, CD audio, DVD video.  I have checked all of the volume and speaker
and sound settings I can find.  The problem exists on WMP, Realplayer, and
Interactive.

Is this likely a sound card problem?

Any good ideas?

Thanks.