You can change the music of the game with a simple trick. If you are on the lose or pause screen. Use the S key to move down to "exit", while the transition is playing, if you press retry, it will load up the game scene with the next music that would play if you had gotten a tape.
The reason for this is probably because when the scene is loaded, it does not use code that "plays this song when this scene is loaded" but instead "plays the next song in a list of songs" where the first song is in the main menu.