Sound problems during load

Hi,

first of all here is my hardware configuration: Asus A7V600-X (VIA
KT600) mainboard, a Soundblaster Digital 4.1 and an onboard soundcard.
Here is the output of cat /dev/sndstat:

FreeBSD Audio Driver (newpcm)
Installed devices:
pcm0: <Creative CT5880-C> at io 0xb800 irq 19  (1p/1r/0v channels duplex
default)
pcm1: <VIA VT8237> at io 0xe000 irq 22  (5p/1r/0v channels duplex)

I have noticed some sound-playback (through xmms) problems during I/O
load for example extracting a big tar/gzip/bz2 archive. While extracting
the sound slows down, starts to stutter and gets very distorted on both
soundcards. The same thing when I try to load a kernel module. I've
already done some testing with my bios and irq settings but no success.

This happens on FreeBSD 5.2.1(-p8) and on todays -CURRENT. I just wanted
to know if there is any fix or workaround available? Would be great.

Regards

-- 
Tobias Aigner