Shoutbox

hey,
i have recently been running my DJ equipment in my bedroom to get a volume i love. i have the cablse to channel my computer into my decks on though to my amp then onto the speakers.
all was fine - no problems.
but now, i can only get sound to 1 half of my speaker system. it isnt the decks/amp/speakers because they are all fine and i have tested the computer with my other speakers (for the computer) and a set of headphones, all to prove the same problem.
i have checked my windows sound settings to ensure the settings were'nt weirdly changed to come through only one side of the speakers, and also checked the settings in "SoundMAX" (my onboard sound card drivers)
could i possibly have damaged the motherboard somehow, i have tested using both the front and rear ports of my computer only to get the same results)
it wouldnt surprise me if my motherboard has been damaged - after all...i have had 2800 watts of volume playing in a bedroom- with a hollow floor beneath me and the bass full, with my monitors bouncing off my desk and everything falling/moving. so i know its possible i damaged my sound card.
any suggestions on things to test to find out though?
thanks.