Hello,
I totally suffer from the same issue. I'm quite surprised that no one could bring a good solution yet. I also wonder that is there anyone who watches 4K movies without any issue
My sistem is Kodi 17.1, Nvida Shield TV, JVC RS-400 Projector, Pioneer SC-LX59 AVR. All cables with system supports 4K-60hz-4:4:4. Nvidia Shield TV is always set to 4K-60hz in any case)
Anyway, my problem is quite same but let me explain once more. Because it's really strange. I'm having 2 type of issues.
1st issue- When i open Kodi i notice that Screen Resolution is greyed out and fixed to 1920x1080. There's no way of changing it. When this happens i get the
same issue 3840x2160 ->1920x1080. So, Kodi downscales 4K to 1080p according to this.
2nd issue- I'm not totally sure, when the system reaches this phase. Probably after i hard-shutdown the Nvidia Shield. So, when this happens Resolution Change section is open and i can set it 3840x2160 or leave it 1920x1080p. Anyway, i leave it still with 1920x1080.
Then i start a 4K movie. And this time projector switches to 4K-24hz automatically. When i check the info screen I see 3840x2160 => 3840x2160. We may assume that everything is allright now.
But i don't think it is.
Because when i start a 1080p movie, projector switches to 4K-24hz again. Info screen says 1920x1080=>1920x1080 but i'm still not satisfied. Because projector shouldn't switch to 4K-24hz while watching a 1080p movie.
So, i came up an opinion that, Kodi makes an upscale for 1080p movie. For 4K it downscales to 1080p and then make an upscale again which causes a non-correct 4K view.
So, i'm totally confused with it. I believe whatever i do, Kodi can't play native 4K movies in all my cases.
What should be the fix? Is there anyone who can play 4K movies properly with Kodi?