Turns out my issue was caused by my AV receiver. The color space ycbcr
setting was set to 8 bit. I changed it to support 10/12 bit and that
enabled full HDR on the Chromecast at 60hz. I still don't understand how
HDR was working before the android up...
I'm experiencing the same problem with chromecast 4k on a Samsung QN90A.
HDR only works if I change refresh to 30hz. HDR at 60hz worked fine
before Android 12
