Feedback loop

So I just got a headset to use with team fortress 2, but I have a problem. When I test it in steam, or in the windows configuration, I get a loop, I'll say something into the microphone, hear it, and then it'll repeat, getting a bit louder and more distorted each time. If I mute wave volume, then the problem goes away, the microphone works fine. But then I can't hear anything. I think I may have done this myself a while back when I was recording internet radio, making the audio output the input.

So what are the default windows audio settings? I'm hoping that will fix the problem. I'm using onboard sound, Realtek HD audio driver.

Edit: things work just fine when I record in Audacity, no feedback problems at all.

What kind of head set is this? This is a rather odd problem since these feedback loops usually only occur when you have a mic and an external speaker playing aloud.

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Spike

http://www.newegg.com/Product/Produc...82E16826179039

That's the headset. When I'm testing the microphone in steam, it'll pick up whatever is playing, music, whatever. Even with the microphone off I'll get the loop.

Edit: Problem resolved, I had stereo mix on in my recording mixer.