Landscape paint brush paints sqaures only [Unreal 5.3]

Hi all,

I have a problem similar the one described in this post:

But there is no working solution, so I created this post. I also can narrow down the problem further.

All landscape paint brushes paint these rectangles (in the size of the grid) on all levels in all projects of my installation. One project has multiple landscapes and it affects all landscapes in this project. It also affects other projects, which worked fine some days ago. It also affects every layer I paint, even the other brushes (smooth, flatten, noise) seem to have this effect when painting.

So I guess it’s a system- or engine-wide problem. I am not aware of changing settings anywhere.

I recompiled the lighting and landscape, checked resolution and material settings, but found no clues.

Has anyone an idea where to look?

Any help would be greatly appreciated.

Best regards