Thanks for the suggestions.
I tried 3 different mini xLR to xLR adapter cables, including retail.
Tried 4 different condenser mics.
Tried 2 ac power adapters.
Different power sockets. Two houses.
A UPS conditioned power.
Camera settings reset.
Firmware update.
All with the exact same result. Loud buzz on XLR mic input only when connected to AC.
Took the camera to the retail store and they said it has to go for repair.
![:-( :-(](./images/smilies/icon_e_sad.gif)