Bizzare Problem with RDP and Audio

Hi All,

I have a problem at a client site that is making me crazy. I've Googled it
for days and can't find an answer. I normally remote into this client site
via a Windows 2003 Web Edition server via RDP. If I need to, I connect to
the Windows XP machines from the server using RDP. The other day I went into
several of the workstations from the server. Everything looked fine (and I
used the default RDP settings). I got a call yesterday that almost all the
machines I had remoted into no longer have audio at all (this is not from a
remote session, but directly on the PC's). When I investigated I could see
that the Audio card looks fine in the device manager (no exclamation points
or red x's) but the area where you would select the Audio card as a playback
device is grayed out and I can't select it as an option. The speaker icon is
no longer visible in the task tray area either. These systems are pretty
much identical and all have Windows XP SP2. They are Dell machines with the
SoundMAX Integrated Digital Audio (on the mainboard). I've checked
everything I can think of. It appears that the audio cards are operating
properly and it's highly unlikely that 4 or 5 computers would have the same
hardware problem at the same time. There are 2 or 3 machines on site that
are not affected (ones that I also remoted into the same way). It's as if
the RDP Audio driver was disconnected after I left the session, but the
regular audio driver wasn't re-enabled.

Any help on this would be appreciated.

Lesa