Sound like a typicall DX8, perf or driver issue....
Do you have by any chance *grin* a Soundblaster ?
Try reinstall dx8 and/or lower the sound hardware acceleration
button one notch or reinstall the driver for your soundcard.
This can happen also with a low end computer, if the proc is too busy
the sound start to have some pain (pentium aren't *really* multi task)
Hope this help ?
Dan