>>8001I don't know what it's called, but I get that too. There's nearly always some piece of music or another stuck on a loop in my mind. Even sometimes when I'm out with my friends I'll just stop getting involved in the conversation to listen to the music that isn't actually there.
Maybe lots of people get it, I don't know. After all, there is that phrase: "it's stuck in my head" that people say after hearing a catchy song.