I don't know if this is a vanilla Jazz2 bug or not, but just out of curiosity I let the main menu of Jazz2+ beta v6.2 in idle just to see all the autoplay Demos. Once in a while other things plays instead of a demo, like the High Scores screen, the intro cinematic, just the title screen before the main menu, and then the Epic Megagames intro.

However, when the Epic Megagames intro plays after being idle in the main menu, it plays with both the short Epic Megagames intro music as well as the main menu music.

This might as well be a bug Jazz2 always had, and frankly I don't mind it. I just wanted to report this bug anyway.