YAY! someone else with the problem!
It appears to be a rather common issue between Via's AC97 and WinXP.
None of VIA's drivers worked for me, I went thru a big list of other manufacturers using onboard AC97, and the one that finally worked was the 'Avance AC97'
That being ALI, I believe.
Sound quality I haven't had a problem with - I have [modesty] excellent hearing [/modesty] and havent had to worry about pops clicks whistles buzzes etc...
It goes thru my home stereo system which has it's own CD player - no noticeable difference in sound quality between mp3s and the cds I ripped them from...
Granted i'm not an audiophile or anything, but i'm, quite happy with it.
Everyone seems to be saying "OMG NO ONBOARD AUDIO EEEK"... i'm not so sure.
Maybe back in the day when it used to pinch system memory like low-end all-in-one mainboard solutions tend to, but nowadays it's much of a muchness - kinda like comparing the sound quality between an SB16 and an SBPRO.
I hope you get your driver problem sorted - take comfort in the knowledge that others have had, and resolved, the same problem
