Hello.
I still haven't found a logical way but often, and only on Atlantic Map I fly below 900 ft AGL, and all is perfect with ~40 FPS in VR.
If I press F10, for example, or using bombs vith the Viggen, I lost all FPS only below ~900 ft AGL and it's still good above.
I have to re-launch DCS and it's working again.......
I can't insert picture here, I don't know how to do....
Did someone saw the same thing ?