Hi tkcentauri - are you broadcasting through Web Broadcaster or Producer? Are you using a built-in microphone and webcam or an external camera or microphone?
If you are broadcasting through your computer's built-in microphone, chances are this is what's happening:
You have the channel up on your web browser while you are streaming live, and your computer speakers on, so you are speaking into your built-in microphone, and that feed is coming out through the speakers, which gets picked up by the built-in microphone as well, causing an endless echo.
To resolve this issue you can either:
1. Close the browser and not watch your stream while you are streaming
2. Mute your computer's speakers so the sound of your stream doesn't come through the speakers while you're recording
Please let me know if that doesn't help your issue.