Apparently my firmware was already the latest but I just enabled beta firmware.
That?s when I realized that pressing the power button on the remote actually launches a pop up menu. It doesn?t go into standby like my old Zappiti. I think I had to press power button twice to go to standby.
As for black crushing, I think it was because I got too carried away with the display settings. I think I set SDR content to 4K 444 12 bit on the Zidoo - because I could. But checking the Zidoo forum, it is recommended to leave it to 444 8 bit - which is what the Zappiti sets automatically. Switching to that made the PQ virtually the same.
I did find enabling DV conversion did improve the overall PQ but for one issue - due to my projector. The last firmware on the 760ES enabled dynamic iris but also introduced severe grey banding on dark HDR scenes. So for 720p low bitrate material, the banding was quite bad with DV conversion. Ended up using DV conversion on HDR material (which would also exhibit the grey banding anyway).