Thanks, Chien. I'll give the CD to my son and tell him it's his to destroy. He'll be creative. :-)

Did you try this before going to another soundcard.
Install the card, answer NO to all xp's prompts to install any drivers or software.
Don't install anything from the Audigy's CD or downloaded updates.
Windows may assign a generic driver to the card.
Then go under device manager, select the audigys properties and then it's driver files display.
Click on update drivers, then use the audigys driver CD to only install the 16bit drivers for the card, the generic drivers.
It's the extra software that gets installed (24bit, the asio drivers, along with resident programs) that is the usual culprit for problems.
You should also be able to right-click on soundcard and select Disable, then you can use the firewire port on the card. The card should also have an internal firewire port connector on it's board, with the correct adapter cable you can add another firewire port.
After I bought a similar Audigy card and had trouble I only loaded the 16bit generic drivers. Just for using the card for playback (although 16bit recording does work). But many times I have had that card in a computer along side of the M-Audio 24/96 M-Audio 24/96
Notice on the Details page there is a ASIO-2 Listing, it's these drivers for the Audigy that I believe is giving you a problem. This is a newer card for 5.1 Audio by M-Audio M-Audio Revolution 5.1
I haven't used the M-Audio Revolution but do use the Audiophile 2496. Not all of M-Audio products have the Vista drivers yet, here is a listing of their Vista Driver/Compatibitlity so far. M-Audio Vista Drivers
You can in XP right-click on the Audigy & disable the card, or just load the generic basic 16bit drivers. Under device manager when you disable the sound part of the card the firewire ports still work. That audigy should work unless the cards having a hardware problem. It's that darn software.
Or just use the sledgehammer thing, that always works.

I'll bet you're right! I'll bet it's not the Audigy card itself, but the ASIO drivers.

I'm going to run sans Audigy for a few days to make sure I do in fact have a good system, then I may just give your idea a shot. I had to manually locate and delete the asio components, even after uninstalling the drivers.

One nice thing - I still have my original Windows installation hard drive. I kept it, knowing I'd need to pull data from it. I could just use it as my test installation.

Great suggestion!