I already reported this problem months ago, but in the wrong section:
https://forum.kodi.tv/showthread.php?tid=331968
I can confirm the temporary solution of Ulvinn,
i've done tests with multiple videos mkv in 1080p at 23.98/24hz and one mkv in 4k at 24hz, on NVIDIA GeForce GT 1030
set the Vertical sync to Fast solves the problem
NVIDIA Control Panel -> 3D Settings -> Manage 3D Settings -> Vertical sync (set Fast)
in fact not only makes the 24p fluid, but also makes more fluid all other frequencies, at least I noticed immediately even on the 50hz.
A point: I noticed that when you jump forward the movie, sometimes loses the right synchronization (and restart to stuttering a bit), to fix it you have again to make a jump forward or backward...
At the moment i can not do tests on AMD Video Cards changing settings in a similar way.
This makes me think that Kodi handles something bad vsync or sets wrong vsync in the Directx 3D configuration.
Better make it known to @
afedchin