Annoying whitenoise sound coming from snd_hda enabled chipset

    I don't know how else to describe it, but when I turn up my
speakers enough (50%+) and don't have any sound playing, I hear a
whitenoise hiss coming out of them. When I change webpages (nvidia
driver is GIANT locked) or do something else kernel intensive it stops
for a brief second, but apart from that it's an annoying trill sound
almost like a mosquito humming around me waiting to be swatted.
    It's really driving me insane... Hopefully helpful snippets follow:

    vendor     = 'Intel Corporation'
    device     = '82801IB/IR/IH (ICH9 Family) HD Audio Controller'
    class      = multimedia
    subclass   = HDA
pcib2_at_pci0:0:28:0:      class=0x060400 card=0x82771043 chip=0x29408086 rev=0x02
hdr=0x01

[gcooper_at_orangebox /usr/home/gcooper]$ uname -a
FreeBSD orangebox.gateway.2wire.net 8.0-CURRENT FreeBSD 8.0-CURRENT
#1: Mon Feb 16 20:50:56 PST 2009
root_at_orangebox.gateway.2wire.net:/usr/obj/usr/src/sys/ORANGEBOX  i386

Comments?
-Garrett