Since it quits working when it gets hot, you've got something in the system with a thermal problem. Damned near impossible to find these. I used to own a delivery service and we used Motorola radios to dispatch calls for deliveries and pickups. I had one unit that would stop transmitting when it got hot because it had been mounted in my van where it would be in the sun sometimes depending on where I parked it. I could run the a/c for 15 or 20 minutes and it would cool down and start working again. The guys at the radio shop couldn't ever find the issue, but I solved it on my own by taking a small, light weight cardboard box and painting it bright white. I would put it over the radio when I got out of my van and when I came back, I would remove it and check in with the office. Worked like a charm. When I replaced the van, I told the radio shop NOT to put that sum beech in my new one. I got a new radio and never had an issue with it. What is happening is when something gets too hot, it's breaking the connection. By the time you pull things out to look out, it's probably been long enough for whatever it is to cool down and reconnect. Good luck solving this problem.