That's funny. That was the very first thing I did: Record a vocal then overdub it. It was terrible (I mean, I did a terrible job). And I could not figure out how to delete it. And even though there was a Mixer Entry for audio, I could not use the mute. It just merrily pegged the meters and ignored me. (I think I see part of the problem in that the pop-up for the mixer doesn't necessarily reflect the instrument you're hovering over.)

Anyway, I found the WAV file and deleted that. laugh