My microphone records output(headphones) rather than my voice?

[lance]

I recently discovered that my microphone (the one i have been using for ventrilo for several months) recently stopped working. It no longer records my voice, rather a static sound. Then after some experimenting with my other computer, I determined the headset was not broken and that this computer records whatever it is outputting rather than my voice. I have tried everything and I would be grateful if someone could help me.