[chrissxuk]

Change to the default/system skin Estuary and restart Kodi.
After that, if the problem is gone, then it's an Amber problem.

I did as you suggested and although it did exit the first time in Estuary, the second it froze again. I think I may have found the problem though it's a specific third party add-on, which obviously I can't mention. By trial and error after disabling one add-on the problem appears to have gone away. I need to monitor this. Thanks for your help.