Thanks for the advice guys- but I know that it isn't the cables because I've tried different ones, and I know it's not the software because I've tried two different programs (Cakewalk, and the standard windows recorder). As for dust, well, I just opened up the comp, meaning to replace the soundcard (as it turns out, the damn comp only has one PCI slot which the graphics card is hooked into, the soundcard goes directly into the motherboard, so I can't replace the soundcard) and gave it a good blowing out so I don't think its dust or anything either.

I may be able to deal with it though. Does anyone know how I can filter out an ultra high EQ such as this "hissing" in a program such as cakewalk? Without affecting the other audio of course...