I managed to sort mine too, but not sound related though
I reinstalled Win7(64bit), run LFS excactly same probs
I then tried WinServer2008 (32bit), and it worked fantastic, but had prob with AVG on server.
So I thought it might be 32/64 bit related. Installed XP 32bit S3, and had sound problems with S3, but LFS played very smooth.
SO I reinstall XP 32bit S2 and *BAM* my LFS S2 unlocks are done for the week biiiggggg bummer
My PC is just about two years old, and all my hardware came with 32bit software, so it might have been the 64bit software that i was using. LFS plays perfectly now, but only blackwood and 12 cars(aaaggghhhhh), but sending mail to "headoffice" regarding my prob, they just might unlock it before friday
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2 x AMD Athlon 2.55gHZ
2 GiG Ram
NviDia GT 8600.
edd