[querty1000]

In addition - i have stuttering on tv episodes with 50 fps. KODI switches to the right fps rate, the TV shows 50 fps, but the episodes stutters the whole time. 24p movies are playing fine on my setup.

You can try adding the following to advancedsettings.xml.
It forces 25Hz for 25fps, rather than do 50Hz, which also didn't seem smooth for me for some reason

I'll check that, too. Maybe my TV supports 25Hz and I don't know it. If not, any other suggestions or known bugs?

Just woundering, all the resolutions and fps that listed in kodi.log, like this:
22:54:33 T:1682223232 NOTICE: Found resolution 3840 x 2160 for display 0 with 3840 x 2160 @ 23.976025 Hz
22:54:33 T:1682223232 NOTICE: Found resolution 3840 x 2160 for display 0 with 3840 x 2160 @ 24.000000 Hz
22:54:33 T:1682223232 NOTICE: Found resolution 3840 x 2160 for display 0 with 3840 x 2160 @ 25.000000 Hz
22:54:33 T:1682223232 NOTICE: Found resolution 3840 x 2160 for display 0 with 3840 x 2160 @ 30.000000 Hz
22:54:33 T:1682223232 NOTICE: Found resolution 3840 x 2160 for display 0 with 3840 x 2160 @ 50.000000 Hz
22:54:33 T:1682223232 NOTICE: Found resolution 3840 x 2160 for display 0 with 3840 x 2160 @ 60.000000 Hz
22:54:33 T:1682223232 NOTICE: Found resolution 3840 x 2160 for display 0 with 3840 x 2160 @ 29.970030 Hz
22:54:33 T:1682223232 NOTICE: Found resolution 3840 x 2160 for display 0 with 3840 x 2160 @ 59.940060 Hz

- are that real resolutions talked back from the TV that the TV can real display? Or is it something from the AVR inbetween the HDMI-line?