I don't want to say something stupid but if I am not wrong there are 2 OSS drivers supporting AC97... they should be VIA82xx and VIA82xx-snd. Again if I am not wrong, Mandrake starts using the first one and if you switch to the second one everything should work fine. I don't remember how to do it because now I use another distro but you should be able to do it from the Mandrake Control Center. Hope I've been helpful :)
See you all, Beppe
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