Just now, I saw a stream of a person playing Game Boy games. The technical setup is like this:
- Real American SNES.
- Real Super Game Boy 2. (Only released in Japan; fixes the speed bug in the Super Game Boy).
- ROMs on a Game Boy Everdrive.
Going through the list of games, he first started "Animaniacs". On the first stage, there was an upbeat circus music. Soon, he stopped playing it, resetting the Everdrive through some button combination on the controller, and started a new game: "Midway Arcade Classics" (the one with Millipede).
The menu music for Millipede sounded right, but once the actual game/stage started, it did not use the actual music for the game. Instead, it played the "Animaniacs" first stage upbeat circus music. He was so baffled by this that he turned off the SNES, pulled out the Everdrive, inserted it back in again, and then repeated that for both games.
Now, Millipede had the right music. Not the circus music from Animaniacs.
How is this technically possible? What kind of technical glitch could possibly make such a thing happen? It's especially weird that it waited to glitch out until you actually started the gameplay, so it wasn't just picking the same song data somehow for any music, which would've made more sense.