I’m interested in what progress you make with this. In that perhaps a simple sequencer beat maker app could be made using UE4.
Surely there is a way to hook up to an on screen knob widget for volume control. If you can figure it out, the next mountain to climb for a sequencer app would be how to effectively create panning left and right (for a panning knob) which also is also a volume issue between the two stereo speakers left and right.
I agree with you this should be a relatively simple thing, unfortunately I can’t offer you any insight on this issue, maybe someday though…for now I just offer your thread a bump and hope you receive an answer on this.