[ChristianTroy]

First plays fine, then I skip back 10 seconds and then you can see the "judder". It lasts for 30 seconds or so, although I didn't record all the sequence. In this video, the issue is not very clear, but I can assure you on the TV is very very clear and annoying.

This is the in kernel thing for smooth 24p playback (CONFIG_AML_VOUT_FRAMERATE_AUTOMATION) that is assesting, if you disable it you don't get it but you don't get the smooth playback.
This doesn't happen with "4k player" or "Mx player" so I don't know why it happens with Kodi, I can only try to get in touch with Amlogic regarding this to see if they have any hint.
What's weird is that I cannot reproduce it every time, some times it just goes smooth immediately, other times it needs the "assesting" time, in such cases I also noticed that pausing the video gives you smooth a playback immediately.