737 overhead sometimes unclickable

Hey guys,Recently purchased the 737 NG 600/700. Even though it's old, I needed a good 737 to add to the hangar and was interested in learning a new aircraft. During flight, part of my overhead freezes, I am unable to click on lights, part of the electrical system, etc. Other things on the overhead are clickable but most aren't. Everything on the overhead works fine until the plane is in the air. I run a home cockpit setup with the outside view on a projector and the main panel on a regular screen. Hope this can be easily resolved. Thanks again!Reed