This is the puzzle!
I’ve been using 2 monitors since I bought MSFS without any of these problems. None at all. Its only appeared after the latest update.
The maddening thing is - the game runs so smooth but I cant do a thing with it. One minute I’m checking out views the next the view camera just freezes and thats it. Game over. In fact the only way out is to kill MSFS via the Task Manager.
The lack of responses means this is not a common issue so I guess I have a lot of trouble shooting ahead of me.