A bug: Classroom_base.ogg is different from Classroom_base_loop.ogg because it doesn't completely replace music.
I'm confused, what do you mean? Is there an error that pops up..?
No... because the music in your Classromm is not completely replaced, so the loop is still the music before the replacement. Your music style is to play the basic song first, then play the loop of the music...
So in the classroom, it will be like two songs in a row.
You may be able to try the game yourself... The game has to have a debug process.