FYI, if I use Chromecast from my Android phone HBO Max app to the Nvidia Shield, I get 4k and HDR with no distortion if the Shield is set to a 12 bit color mode. Atmos audio works via Chromecast as well.
Agreed. It is the only app I have ever run on the device that required that. When I switched it to 4k 23.97 Hz with 8 bit color (mode not labeled as "HDR ready"), the color problems went away and my projector indicated that the signal it was receiving was HDR.
Heads up for viewers with Nvidia Shield Android TV devices. You must select a viewing mode with 8-bit color (and color space set to "auto") to watch HBO Max in 4k with HDR10. If you select a 12-bit color mode, the content will play (so far just Wonder Woman 1984), but the color signal will be...