Suddenly Low FPS Due to GPS?

I haven’t been on MSFS for a month or so and I’ve just updated to the latest version and now I’m suddenly getting really low FPS with it saying that I’m limited by the GPU. However my GPU is showing next to no useage in the Task Manager so I have no idea what’s going on?
System is
RTX 3080 GPU
Ryzen 9 5900X CPU
16GB RAM

I’ve tried both DX11 and DX12, NVIDIA reflex low latency on and off. Terrain LOD is set at 100 as is objects LOD and I’m ony on high end. If I change to medium I get maybe another 10fps. Anyone know what could be causing this as before I could get at least 60fps in the same area on ultra.


image