Kodi 21 playback issue

Hello everyone,

I have a major issue since the v21 update, that is most of my movies won’t playback any more (device is a fire stick 4k max). The movie starts, then after 5-10 seconds just stops, or if I try to skip ahead/back it just stops. It happens when starting them via library as well as when starting them from their folder.
It happens on some files, not on others. It happens on movies that have played before as well as on new ones.

This never happened before I updated to v21.
I even checked with my older fire stick which still has 20.0 installed, and the movies in question do play there without any problem.

I have uploaded a log file to paste.kodi.tv (I don’t know if this has worked): https://paste.kodi.tv/hujepowofu.kodi

Is this a known issue? Has anyone else experienced this? Is there anything I can do to fix this?