Well, I have a theory that some may not like but, there was a 45' rv parked in this group of 4 supreme sites. The 45' behemoth left today and what do you know, no power issues at all. I suspect the 3 roof airs, washer, dryer, who knows what else dragged us all down. This is the second time that I was lucky enough to be parked next to a 45' rv and had power issues at this park. Soon as they left, everything is back fine and dandy.
I was fortunate enough to have a pd50 surge system installed that protected me from under-voltage but the other folks probably didn't have a clue as to the damage they were incurring with the low voltage.