My first thought was- Could it be an alien space ship in disguise?
If it is plugged into power I guess it's possible the roof may be creating some sort of jamming. But that would mean there would have to be some current going through the roof which means a possible short. First thing I would do is to unplug it from power and if you have solar panels disconnect them.
I remember reading where a motorhome became charged with electricity when it was parked under some high power electric lines. The owner would get a small shock when he touched the skin of his MH. Once he moved the MH out from under the power lines the shock went away.
Do you have a Cell signal booster or WiFi extender they shouldn't cause interference but if the frequencies are close who knows what might happen.
I would unplug all electronics and disconnect the batteries in the trailer and then start reconnecting one by one to see if any are causing the problem.
