I thought so too .. I thought it was actually called "soundprint".

By the way -- the reason I can't trust tags is that you can change the tags outside of jEmplode but it's still the same song. So I have to create a hash of only the music portion of the file and store that with the tune on the Empeg. That way when you drop a tune again, I can hash the tune you just dropped and look for a match. But you're right -- the bitrate change would break that.

I'll go hunting for a soundprint...