I run Kodi 18.9 Leia on an NVIDIA Shield TV and I was having major issues getting all of the different resolutions and frame rates to work seamlessly with the AI upscaling without having to change settings to watch 4K and 4K HDR. I also wanted to keep the Kodi GUI at 4K.
I scoured the internet but didn't find anything that met the requirements of what I was trying to accomplish. I have since figured out a solution and I'd like to share it to prevent the headaches and frustration that I experienced. Turns out the key was whitelisting all the 4K resolutions EXCEPT the 4K resolutions that Kodi will switch back to after playback is stopped. Here are my settings. I have a 4K Samsung TU-7000 Series but I hope this will work with your 4K TV.
NVIDIA Shield TV settings
- Settings > Device preferences > Display and Sound > Advanced display settings > Match content color space - make sure this is on > Custom display mode > click Set to default (3840x2160 59.940 Hz YUV 420 10-bit Rec. 2020 HDR10 Ready)
- Back > Back > AI upscaling > click AI Enhanced > click Medium (default)
- In order for HDR10 to be available you'll need to turn on Input Signal Plus for the HDMI in the settings for the TV (Settings > General > External Device Manager > Input Signal Plus > click HDMI port that your Shield TV is using)
Kodi 18.9 Leia settings
- Settings > Player > Videos > under Playback click Adjust display refresh rate > click On start/stop > right below that make sure Sync playback to display is not selected > scroll down - under Processing, make sure Allow hardware acceleration - MediaCodec and MediaCodec (Surface) are both selected
- Back > Back > you should be on Settings main page > System > Display > Whitelist > click all 3840x2160p (4K) resolutions EXCEPT the top two (3840x2160p 60.00Hz and 3840x2160p 59.94Hz)
- Back > Resolution > click 3840x2160p (this will set the Kodi GUI to 4K) > Refresh rate > set to 59.94 > Delay after change of refresh rate > set to 3.0 seconds
- Restart Kodi
You're all set. Kodi will now be able to switch resolutions and match refresh rates seamlessly so that you can watch 4K and 4K HDR content. It will also leave the resolution at 4K and match the refresh rate while watching 1080p and 720p content so Shield's AI upscaling can do its thing. I honestly don't know why this works but it does. Hopefully it saves you a few headaches.