With fw 1412 all of my hevc 1080p movies are not black but grey .(no change with full or limited output) It uses wrong color. Another bug ?
I confirmed the issue you are encountering with FW 1.4.12, and the issue is not there with FW 1.4.4. With FW 1.4.12, there is an extra setting option "HDMI Range Mode" at the very bottom of Display setting. If it is set at auto or Limited, I see the same issue as you are seeing, if set to full range 0-255, the issue is not there. My settings are: 2160p@60Hz RGB=444, deep color =auto, parameters are all at 32, TV/monitor is seiki 43"
Ok...i have only 1080 tv, setting full range ik ok for hevc but then all x264 movies are too dark. So i have to switch always . All ok with fw 14.6.