Scratchy Effect when trying to record with audio?

I’m trying to do a cover for a song, and when I record my voice by itself it sounds fine but when i try to record my voice while the audio is playing the output comes out very scratchy and only gets some of the parts that I recorded. I could just record my voice only then input the audio file but it’s difficult because it wouldn’t be in sync. Please Help!

note* I use a Conexant SmartAudio Mircrophone if you need to know though its probably not important.

You could set up for Overdubbing, and conveniently enough, I wrote some of the instructions to do that.

You should probably start with the one on the bottom – Fake Overdubbing. That one’s the least crazy or expensive.

http://www.kozco.com/tech/audacity/overdubbing/overdubbing.html

That one has you using your built-in microphone and you would substitute your own microphone, but the principal is the same.

Koz