Weird "new folder" issue with videos

[dfkt]

This is an issue I had since x.53/x.54 messed up my D2 and I reverted to 2.51 (Tcctool, Panasonic formatter, the whole shiznit). Now I'm running 2.54 without errors, but this weird issue still persists:

All videos I convert play perfectly fine on the D2, but whenever I create a new subfolder in the video folder and put some videos in there the D2 either skips over those videos, or crashes to a "kernel fault" screen, needing a reset.

After that, when I plug the D2 into the computer again and just change the folder name to something else, the videos play perfectly fine. It's always like that, no exceptions.

Example:
I create a folder "D2/videos/test1" and put videos in there, the D2 skips them or crashes.
If I then rename the folder to "test2" the videos play fine.
After that one renaming there are no more issues, I can put new videos in that folder and they always play fine.

Did anyone ever experience this issue? Any fixes?