[YinYang]

Log submission details are in testing note #9 of the first post.

Alternatively (and assuming Kodi is still working), go to Settings > LibreELEC > System > Submit Log



@YinYang many people don't have the time to work with zipped logs - for instance they might be reading your post while commuting and using their phone etc., so please use pastebin sites where possible as this means your logs are much more accessible.   

 I sent you the logs again after your instructions!   

 In your above kodi log, it gets clear the kernel driver also only gets 1280 or the 1440 mode - there is nothing kodi can do about that. Find the latest build where it worked and then a bug can be filed with the kernel. Though: I am really wondering that such an issue occurs on a very old lts kernel. Make sure to reset your TV settings / change HDMI cable, just to be sure.  

Good morning @fritsch So I can rule out that it is because of my TV settings because I know someone else in the Kodinerds.net forum with the same problem and similar hardware.

Does that mean that I can not reasonably use the current Kodi with my quite new hardware because of new kernels? I think that's a pity because I have bought extra this mini pc to be safe for the future. I'll probably have to disconnect from it and buy me a Odroid c2 where there are hopefully fewer problems.