Jukebox music pause when game is paused with "Escape" (that's a fact).
When the advancements menu is opened, the game is paused (that's another fact).
However, the music from a jukebox still plays in the advancements menu, which is illogical (how can this jukebox play if the game is paused?).
This is simple to reproduce:
Place a jukebox and put a disc inside, then open your advancements menu. You'll hear that the music still plays.
Music is powerful. It cannot be stopped.