VP9.2 is currently not supported on any Android TV device as Android TV is mainly deployed on cheap devices from the Far East. And Sony/MediaTek can't get their own act together. Both really bad Android TV integrators.
Huh.. So the mythical Nvidia didn't even bother to implement the SW decoders for vp9.2? Not that Apple is in a different boat, right now. Actually the Apple TV 4K doesn't currently support vp9 at all (losing most of the content in 4K). Same for macOS (although the vp9 video play on Chrome at 4K, killing my MacBook Pro i5 CPU).
Well, let's see what will happen with this Mi Box. Because at this point the only Android devices playing YouTube in UHD HDR are the Chromecast Ultra. I have read Google had to turn down the resolution on mobile with HDR because.. the videos were stuttering!
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