A complicated issue that I am struggling with, I am unsure if it is the hardware, windows 98 or the creative drivers.

For the first 3-15 minutes of uptime, all sounds on the computer will work. After this point suddenly the sound effects and system sounds stop on whatever game I am playing. Midi and dos emulation sound continues to work. Restarting fixes the issue, but it just stops after some time again.

This is a new 98se build made from spare parts.
Latest unofficial service pack 3 core only with a couple choices relating to ntfs and usb.
Asus cusi-m
pent 3 1ghz
64mb ram (4 dedicated to integrated graphics)
Soundblaster audigy 2.
WDM drivers. dxdiag says ctaud2k.sys 5.12.01.0283 is the main driver. If I use vxd then for some reason most win 3.1 games do not get a full range of sound, but it did not appear to crash at all when tested in other games. The motherboard has a built in sound system, it only seemed to have vxd drivers, it too would not play the 3.1 sounds, which is why I put the soundblaster in. It did not stop working either. It is currently disabled in bios.

I've uninstalled stuff, messed with driver versions, tested games out to determine if there is a difference in randomness, a bunch of other minor stuff. Have not reinstalled OS and really don't want to yet.

Would appreciate ideas.