Video files flicker, stop and MP shuts down.

[Orfanomondo]

I installed MP 1.12.2 64-bit for Windows 11
Suddenly today mp4 files, that I have played before without problems, started to stutter/jitter/shake (don't know the correct term). The image flickers, stops, and after a while MP shuts down completely. I have to restart it. No problems with image files, only video. I have video thumbnails and preview enabled.
In the ini-file I changed: UseInternalVideoPlayer=false, but it did not really change much, the videos play smoother for a while, but then MP shuts down again.
I played some more mp4 files and noticed that shorter files 30 sec - 2 min, played without problems. When the videos are longer 10-20 min, the problem is more pronounced.
I can play the same files with Windows Mediaplayer.

As my Kalmukian friends say: What to do?

[Orfanomondo]

Forgot to say, I did not knowingly change any settings, video or otherwise.

[Orfanomondo]

I AI:ed (there must be a verb for it by now) the problem and in its infinite wisdom AI suggested I download new updated video codecs, which I did. It seems to have solved the problem, for now. I'll keep following the issue.
https://www.codecguide.com/download_k-l ... k_mega.htm