Welcome to VIA country. Most people blame their sound card problems they have with Creative Audigys on the Audigy.. but most do not realize that VIA doesnt work with many PCI devices properly. My KT266A crashes when lots of information is being transferred over the IDE bus.
VIA sucks, your only real option is go SIS or Intel.
Athlon 1700+, KT266A, 512MB PC2100, Geforce 3, Audigy, Z560s