I own 2 airplanes, one purchased from JA. I called...

I own 2 airplanes, one purchased from JA. I called to ask a tech about a radio transmission problem. I was told that they couldn't answer a question about that. A radio does 2 things; transmits and receives. If a RADIO shop can't answer a question about one of the 2 basic radio functions, do you really want to have them do ANYTHING to your plane?