I have a dedicated circuit for my computer rack where my servers, routers, etc. are... It started loosing power very briefly up to 5, 6 times a day. My UPSs email me when this happens. Last night I happened to be standing there when the power cycled. I went to the power panel and checked the breakers. Nothing had tripped, I felt them and they where hot. 130 degrees hot according to me temp gun. My FIL came over and we took it apart. There was a screw where you see the white spot on the breaker in the pic that was loose. We fixed that up, installed new breakers and are back in business. They are running just under 70 degrees now under load.
Scary thing is that the breakers didn't trip and you couldn't see anything out of the norm when you looked at it. I'm glad I felt them to see how hot they were. This could have been a fire hazard!
Check your panels, especially if you are having weird issues!