Big problem in Volumetric Light?

When moving the camera in sequencer, volumetric lights will dim itself at certain angles and distance. Then i discovered sliding the editor window will have same effect. In serious situations it is like turning an off switch to the lights. Below is a video screenshot: ( especially obvious nearing the end)
I hope this is not a bug, cause if yes, it will be a very serious one. Sometimes the renders becomes dark all of a sudden, is this the cause? This however does not happen in editor, but only in sequencer camera view.

That’s probably due to eye-adaptation/autoexposure, or due to vignetting, check your post process volume settings

I have unticked all autoexposure settings, as for vignetting i didn’t have them on at all, it’s still the same problem. Here is another video capture of the problem getting more serious.

I have the same issue. but I’m guessing that should be because of the nature of Volumetric Fog. not sure but I guess it’s a Screen space effect and you’ll see the effect as long as your camera can face the light source. if it gets culled by other objects in the scene then you won’t see the effect.

This is definitely incorrect, but other than a weird autoexposure/adaptation setting I can’t imagine what’s causing it.