Not sure what it is, as everything has been fine for months and months, I will see if v4.7 fixes anything or 11.30 beta is buggy. but in general, this is an out of the blue issue again.
my iMac works in top shape for all other things.
I tested many toggles on the SMP interface box, but nothing changed the issue, unlike a previous time where disabling shadows on water made the issue go away.
uninstall SMP and use x-plane default weather and there isn't this issue.
that is all I have to help you