YOu may want to check your ATS. Where ever it is go to it and listen to it, It should not be chattering. Also check your whore power cable plug for how warm it is while plugged in. Then pull it (after opening the circuit breaker) and look at the plug itself and look for black or burnt marks on it. Now while you have this disconnected, Open your ATS box (make sure you don't have the generator running or the invert on) and look at all the connections in it. There should not be any melted or burnt cable ends. While in there make sure all the lugs are tight. IF you have any of the symptoms that I mentioned then you need to get them fixed prior to plugging back in because they are signs of high resistance or high current draw.
All of these things can lead to a breaker tripping which can also lead to fire.
Good luck and happy hunting down the issue.
I more thing, if you don't have a Surge Protector then I would recommend that you get one, for this too can save you lots of money and heartache down the road.