I have the same issue, I think (7.90.004 on WeTek Core).
I use 'Adjust Display Refresh Rate' without 'Sync Playback to Display', my TV can do 24, 50, and 60 Hz.
Playing a 23.976 fps 1080p AVC file with refresh rate 24, the TV confirms 24p mode, and everything starts smoothly.
After about 50 seconds (and always at the same point, when starting from beginning), there is a brief stutter (like multiple frames dropped) for a fraction of a second,
then everything is fine again. This repeats every minute or so.
When I seek before watching the same scene, it plays without stutter, but stutters later. The same with basically any movie I tried.
I tried disabling hardware support, with no effect.
What can I try to narrow it down?
kodi.log
mediainfo.txt