I came here as I had the same problem. I have an 83" Sony A90J which has Prime built in. All my games were flagged as 4K UHD, when I logged in and played them they were terrible quality? Surely I don't have to stump up more cash for a Firestick to get Amazon 4K UHD? I have an Amazon app in my new Panny 9000 Blu Ray player, perhaps that will be better, but I am shocked the Sony Prime App outputs just HD?Just watching live prem league action on Prime Video between Liv vs Leicester.
It says 4K and HDR but on the actual content, it labels in HDR but not in 4K!
But, when I watch it; it's just in HD and not HDR?!
What's going on.