Okay, here’s something I have in mind : a Material that reacts to sound, music channel only, changing colors and intensity (mostly intensity, I can guess for the colors). Kind of like an equalizer, just for design purposes.
Any clues ? 
I’ve not messed with materials but you can get many variables from the Sound Cue class. Then with some logic you can have a material with parameters change.
There is an audio plugin with which you can get the pitch and other values -> you can “feed” that into a blueprint + control the material with that 
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