Bug with some lighting in some scene while play in PIE

Hello all, I got a weird issue with some lighting in unreal, when i run my game, sometimes the shadows are broken (too dark and not as usual), and if I got in the editor and toggle the visibility of the some folder, the light get fixed … (the folder is only static meshes placed in the world). We use a very simple setup for our light, 1 sky light, 1 directional (90 degree form the ground) and both set to dynamics, so not baked lighting… not sure what cause the issue, any ideas ? ^^