hmmm...strange, cause I have a slower system and sound is perfect for me...using Azimers v0.30 plugin (Driver Rev 2.2)
you do have the Fram limit on and such right?
Try increasing the buffer size or as in my case decrease it to it's lowest setting, but I have aq SB live to so that does make a difference even if the SB live drivers for XP are crap.
BTW my system specs are:
Geforce 2 GTS
Voodoo 5 PCI
20 gig HD
Biostar MB (Yea I know, can't overclock with it)
320 MB ram