Schemas/structures of jsfb files?

[MrBabbage]

I know Meta is handling some of these based on some research, but I wondered if there were any definitions of these out there?

I'm mainly trying to see if I can work out what the currently undefined data in the Audio/musiclist.jsfb and wwiseevents.jsfb actually does, so that we don't have to inherit the fading and looping behaviour of the original music ID when modding themes.