sound issues in win2k

im trying to fix this problem for a friend...
its a compaq presario running win2000 prof.

anyways the sound output (onboard audio) is very very weak... so i goto the sounds and mutimedia control panel and the volume slider is at the bottom so i mose it up and the sound output is boosted (much better) but then it goes back down immediately.. i have to hold the slider at the top/right with the mouse or it will go back down/left automatically.... i reinstalled the drivers and everything


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epox 8k7a
amd 1000mhz
radeon le