So just to add some closure to my problem, i finally resolved my issue. turns out it was just some sort of ground loop issue. the problem, however, was that i could not find any good grounds that would cancel out the noise. i got a tip from a guy in the maccar forum that led me to this nifty little noise filter here. after hooking this up and ditching the imic that i was using, everything works perfectly! no noise and sound quality is still great! Just want to say thanks to everybody on this thread for your help.
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