Quoted from PinMonk:If it's giving you shots for one song and playing the music of a different song, that's definitely a bug that should not happen. We did it accidentally a number of times before working out how it was happening so it was reproducible. If you spend 10 minutes or less doing what I describe, it can be done on yours, too - reliably.
It's a bug. You have a switch in the shooter lane. Once you plunge the ball that switch opens......which should lock in song selection and shots regardless if you hit a switch on the play field or not.