Graphics artefact

[GoogleFrog]

Look at the top left of this image. There is a vertical line which has a different brightness of wall on either side. This line moves horizontally across the screen in a very noticeable way as I walk down the passageway.

[GoogleFrog]

A similar thing happens here with the rectangle of brightness in the middle right and lower right. The rectangle moves up and left as the character walks right.

[GoogleFrog]

Another example. Vertical line across the screen.

[gajop]

This is caused by dynamic lighting, most notably the small lights that are placed all throughout the map.
I tried to hide it as best I could but I guess it still remains.