VR - objects and scenery go missing

[KLXTwn]

Flying over the whole of the Germany map I noticed that objects ( buildings, landmarks, airports and accessories, ... ) and complete sceneries disappear.
It happens in VR and is not random, the same objects or buildings will always be affected in the same way.

What happens is when flying you will see an object and suddenly that object will disappear and leave an empty spot on the map,
or you will notice an awkward empty spot on the map and suddenly it will be filled with and object.

These objects being visible or invisible depends on the angle you look at them, by changing the viewing angle ever so little the
object might appear or disappear.

I attached two screenshots of the same spot on the map, one with and another without the building ... difference was the viewing angle.

Exactly the same happens with complete landscapes ( like flying over Berlin half of the city will disappear ) and it will seriously affect performance. Stable 90FPS will drop to 60FPS with light stuttering but once you leave or don't look in that direction performance will return to a stable 90FPS.