Pull the switch for your lights out and have a look. If it is like mine the panel is only held in with 4 screws and look at the back of the switch that controls the lights. In my 2011 36RE the switch overheated and was melting at the connection.
I have found that when I was using my 12v lights and the inverting was kicking in the lights did change in intensity a small amount however, after changing to L.E.D. lights the issue has gone away.
Glen & Robyn (A.K.A. Puff & Crickit) Full Timers..
2006 F350 6.0 with 3.73 gears, 4X4, Extra-Cab Long Box, Oil/Tranny/P.S. Coolers. Coolant filter. SCT Livewire.
2011 Cedar Creek 36RE, Auto levelers + too much to list..!