Microphone Playback or mixer?

Hello,

I have been having this problem for a while now. I have a usb microphone, and I broadcast a stream on the net. However, viewers of my stream can't hear my voice, because my microphone is a usb microphone, and windows XP doesn't seem to support mixing the usb mic with the output audio.

I've looked everywhere for either of these types of software, and was unsuccessful:

1. A simple software that will playback the microphone audio to the output audio. I don't mind hearing myself talk over the speakers, as long as the delay isn't too bad. I found a piece of software on soureforge called babbleback or something, but that one only supports a minimum of 1 second delayed playback, and it has no volume options.

2. A software mixer that can mix my usb microphone audio with the standard output audio. Once again, I will hear myself talk, but I don't mind if the delay isn't too bad.

Any help is greatly appreciated. Thanks =)