When you sing a song in your head, stop, and swear you hear it playing in the background.
Person 1:Doo, doo, doo, doo, doo... doo.... dooooooooo!
Person 2: Please shut up.
Person 1: Fine.
Person 1: Did you just hear that?
Person 2: Hear what?
Person 1: The song I was singing I just heard it playing!
Person 2: Nah, that was just ear music