Found the problem. I had a bad 30 amp breaker that was sending 109 Volts to one of the inverters. I traced power from the 50 amp plug thru the cable...
Not a direct comparison but...
I have experienced low voltage on one leg and not the other and found the common power wire (white color in household...
I checked both invertors when unplugged from 50 amp, had 120 volts on both of them. I didn't check them when plugged in. Will check a few more things...