Static noise in ASUS laptop

[Rafael Laboissiere <laboissiere@mpipf-muenchen.mpg.de>]

[ N.B.: My problem is perhaps not specific to Debian.  If it is the case,
  please, point me to the place I should look for help. ]

I am having noise problems with my sound output in a ASUS S8600 laptop
running Debian unstable (kernel 2.4.16).  I have installed alsa
0.9.0-beta10, but even with the alsa modules unloaded, I hear a lot of
static noise through the speakers and, particularly, through the earphones.
Noise appears when the hard disk is accessed or when I move the cursor using
the touchpad.

Looks like I have a hardware problem or a interference (irq? dma?) of sorts.

Do you have any clue about how this could be fixed?

[ Please, Cc: replies to me.]

-- 
Rafael Laboissiere