That an interesting thought, I tried the Onkyo music app because of good revues. I’m not sure if UAPP works the same way but the Onkyo player requires me to import my music. The issue seems to be that Amazon has a proprietary encoding (for DRM reasons) that Onkyo player can’t decode so I ended up importing a bunch of gibberish.
What I hope is someone will read this who has encountered the same issues and provides a forehead
slapping 'Why didn’t I think of that" solution.