I bet this is a really simple error of me here,
Hi,
do you use mirror shader in the level?
I while ago I reported a bug related to transparent/overlay shadows (using the stencil buffer like the pssm shadows) when mirror is created in the scene. I think it has not been resolved properly, but don't remember exactly, it was at least 2 years ago.
i tested this without any Shaders, ore somthing,
Here is a simple Level with the same Bug
But thanx for the awneser