If I play a world for a while and then go to the main menu the music doesn't stop. It just plays over the main menu music. If I start a new world, I get two soundtracks on top of each other, and so on. It becomes quite annoying. I'm not sure if it always happens but you should be able to reproduce it because if it doesn't, it happens a lot.
Environment
I've tried it under Windows 10. I can also try it under Linux if you like but I didn't bother because I think it's a safe assumption that the behavior there is the same.
Duplicate of MC-35856. Please use the search function next time.