Did you ever find a solution or is it SU14? I’ve been having this issue, as well, as you described. The graphics freeze up, the CPU processing goes to 0 for FlightSimulation.exe and it can lock up for anywhere from 5 seconds to 30 seconds and can do it 2 minutes, then 5 minutes, then go 10 minutes, the back to 5, then back to 10, then 2, etc., with no rhyme or reason. I’ve cleaned out the Community Folder to no avail. I’ve uninstalled and reinstalled, uninstalled and wiped out everything in AppData with no luck.
My next step was to format the PC and start over, but I want that to be a last resort.