Vista - extreamly heavy distortion

this is the third time vista has done this to me, i was just sitting there, minding my own business listening to wmp or playing wow or something, and suddenly my speakers spewed out the sounds of 10,000 angry demon monkeys roaring at me, so loud it almost gave me a heart attack every time, then about one month later my speakers work again.

at first i thought it was my speakers so i bought a new pair and it did it to them too, so i got a set of headphones and they didnt work, so i got usb headphones, only those work because they use a different sound card (in the control panal thingy), and after a while the speakers just work again, i would really like to get this fist in less than a month

the speakers are C-media CM6501 Like Sound Device, im a noob so explain this as you would to a child lol thanks in advance

i forgot to mention the headphones are microsoft life chat lx-3000, i dunno how to updated drivers for speakers so if that's the problem could someone show me how to do it?

wow, they work again...ok this is what i did if anyone else has this problem, i dunno if it is what caused it or what but while i had the headphones running i changed headphones to default and i pressed test audio on the speakers and they worked...so...i dunno...if this happens again and that doesnt work you will see me here again though hah!

guess what...me again, and the damned things are at it again. and no, what i did last time does not work..any clues?