Sometimes that CPU warning is a fluke. Unless it happens a lot I wouldnt worry about it. IOS that is current now has been trouble free on my apple stuff. So I am still betting on a hardware issue, or a phone that has limited resources available that is causing the image problem.
You may be right. I’ll fly again after the update and see what happens. If it comes up again and I can rule out heat or other external issues I’ll just upgrade my phone.
I thank you for your input.