Part of the image is fuzzy - CCD burning?

On two of my cams (one D16 night optic pano and one D16 night optic with two wide angle lenses) a particular part of the picture (area) always remains “fuzzy” (unsharp) as if that part of the lens or the exterior lens protection was dusty or dirty. This was not the case when the cams were new. It is certainly not due to any settings of obscure areas that I have created and I couldn’t imagine that the areas are “out of focus” given that I have used the focus aid to optimize the focus of the lenses when the cams were installed. As both cams are mounted underneath a ceiling they are not easy to reach to inspect them closely. However, when inspected from a few meters distance, none of the exterior cam hoods show signs of dust or dirt.

I am wondering how sensitive the CCDs of the cams are to intense light. Could it be that reflexes of a strong street light or reflex of sunlight may cause “burning”? Is there a way to check the quality of the CCD, i.e. if it has been damaged?

How could I possibly check and remedy the problem?

Example 1.pdf (1.6 MB)

Example 2.pdf (6.5 MB)