I have a friend who recently installed a GTX345 for his ADS-B in/out solution. As is required, a test has to be submitted to qualify for the FAA rebate. The only thing that fails is the (Air on Ground) parameter below during an airborne test. This failure stands between my friend and his rebate. The avionics shop says Garmin says it's no big deal. Any ideas on what could cause this? I have seen the report and everything else passes. The test result is from the Airbone 1090 analysis.