I have two airplanes with Garmin GTN 750 units. Awhile ago I determined that when I turned on my iFly 720 it would take down the Garmin GPS (it would lose all satellites ). When I sent the unit to Adventure Pilot they said that the mother board was toast but they would sell me a new iFly 740 at a reduced price. I took that offer. Well, yesterday we turned on the iFly while flying across Nevada. My 750 immediately displayed a number of warnings -- GPS Lost, ADS-B turned off, no terrain information ... Adventure Pilot says they have not heard of this before. But it happens with both of my planes (one a 206 and the other a 182). Has anyone else seen issues between an iFly and other GPS receivers on the aircraft? I worry that people with an ADS-B system with an internal GPS could go offline without any indication to the pilot.