The hum was coming from one or both the transfer switch and as long as you get power into the coach now you are fine. The other would be from the inverter/charger and you would be charging the batter bank. Check to be sure you are still charging the housem batteries and if not check circuit breakers in distribution pane as on the inverter itself.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7