Welcome aboard shipmate!
The combination of two of the three major power draws in your camper having weird symptoms makes me think you have a issue with ground wires in your power circuits. Does your A/C show anything weird? (like blows colder when you flush the toilet...LOL, that was a joke, but does the AC act up?) I would be checking all grounds at batteries and inverters.
Thom & Rose
The problem child: 2014 Voltage 3950
The problem solver: 2017 Tiffin Breeze 32BR