I’ve used level streaming to achieve this.
Mathew Wadstein’s YouTube was the best help though it does go into further detail around loading screens and loading in levels. It’s a few years old so for the UI menu and loading levels part I needed to do some tweaking but all I’ve done for the audio is loaded the music from the persistent map’s Level Blueprint.
I’m only a few days in to making my game, but I plan to run all of the music from that. I can then load and run audio for each map within those maps. I’m hoping as well that this approach will save some time on mobile loading times 
A link to Mathew’s tutorial:
