i had the same problem with heavy stutters on ground and also in the air with PG turned on so i had to switch it off.
The solution is very simple, i have posted screen shots from facebook. What you have to do is locate and delete the following file and folder…for safty reasons just copy them for backup, but as far as i was told after deleting them and when you restart the sim they will recreate them self again…dont ask me more as im no expert on this but this solution works as i test it my self and now FINALLY im able to have PG switched on again!
