It sounds like overheating to me. I would spot check the basking side to make sure that bulb wattage isn't too high and you can ditch the cold side 50 watt bulb unless if your house is freezing. The cool side should be at least 80 or below but preferably in the mid-low 70s. It can drop as low as 68 at night.
I would also highly recommend replacing the freeze dried crickets and superworms with live crickets or preferably dubias. Freeze dried crickets aren't nutritious and superworms are better as the occasional supplement. It sounds like you have a nice set up for him and just need a minor tweak or two to get it perfect.