What kind of peeping? Does it come from the PC speaker, or is it a mechanical thing, or from your speaker, etc? My sound card gets interference from my cooling fans and I'll hear a little crackle. It might be intereference from another source.
Pentium IV 2.4C Northwood- M0 stepping @ 3.2GHz HT
Air Cooled w/ SP-94 heatpipe & 92mm Vantex Tornado at 45C
4x256=1gb dual-channel 2-3-3-6 OCZ PC800DRAM @ 890MHz 3-4-4-8
MSI Neo2-PLS w/I865PE & SATA @ 4x267=1068MHz
BFG GeForceFX 5900@485/967MHz = 6284 3DMark2003s; dual-head 21" CRT & 19" LCD