"Parameter is incorrect" - XP Sound Card

I have a XP home edition PC. I have previously had it working fine,
with an ATI TV Wonder board and the on-board sound working. (The mother
board is a FIC au13). Last week, during a automatic XP update, the
sound card stopped working. I used system restore to roll it back
before the update, and the sound card would work again.

Anyways, the windows update breaks the sound card driver. If I try
reinstalling it, I get "parameter is incorrect" error. I tried
installing a different sound card, after turning off the on-board sound
in the bios, same message. I tried "sfc /scannow", same message. I
looked at the setupapi.log file, and it fails the parsing of
[kp.registration](which appears to be in ks.ini) in the
DIF_INSTALLDEVICE section. I checked the registry and tried located
the right section and setting the key permissions, same problem.

I tried disabling the ATI board and uninstalling the ATI driver, still
no sound card. The ATI board reinstalls fine. I tried updated drivers
for ATI, motherboard, and the other sound card I put in, still no
sound.

I am guessing there is a parameter that is supposed to be in the
registry somewhere that is used by the ks.ini that is not there.

I am at a loss to know what to do without reinstalling XP.