Emerging buildings

Hello all,

I run P3D V3. I've had ftx global base for 6 months now, and after a reinstall of Windows I've started to notice buildings and trees coming out of the ground if I zoom in...obviously this is at my LOD Radius which I have checked in my config, and is set by default at 6.5 miles. I was wondering if all of this is normal and if I was to increase my LOD Radius, would there be a loss of fps etc.

Thank you