Do I need a new soundcard?

[Riskwise]

I use a mic with a friend whenever i play WoW.
I started to play again after like a 4 month break and he says that my voice is coming through so scratchy it's almost inaudible. I go into sound recorder, record myself and listen and it sounds just like he described. I switch mics, and the same thing happens. So, long story short, i want to use a mic on my computer, but my computer is somehow screwing up on its end, not the headset end. Does anyone know what could possibly be the problem with my computer and if there is any way to fix it. I have no idea what could even be the problem, could it be my soundcard?

PS. Playing music and other audio is perfectly fine, its only when i try to use a microphone.