So in an attempt to eliminate a corrupted install causing these spikes and seeing that no further updates were coming post Beta 12 I decided to do a full re-install. What I did:
Deleted ‘One Store’ folder.
Deleted user config file.
Deleted all items from Community folder.
Complete download of all assets (scenery/planes/bush trips/etc).
Did not download any word updates or extras, i.e. totally vanilla install.
Started MSFS and selected Ultra settings (RTX 4090/i7 12700K should handle that surely!).
And yes, spikes still there in same locations as before…
So I repeated all the above steps on a second PC (it was a long day!) and yes, spikes still there.
I’m now convinces this is something in the software and not due to my settings or system.
Remember: My settings have no live weather, no live traffic, no PG, 30fps and vsync. My system is hardly breaking a sweat!