The screens are ok, subscription and tune, despite the weak signal. It may be an occasional problem, lack of traffic information in the RDS signal, intermittent failure tuner (happens a lot in GTM25and 35 cables) or some unexpected blockage in the firmware update. For this last situation, just go back to the previous firmware and check if it works and then reinstall the 34xx fw and check, it should work. For failure tuner you should observe the screens Traffic tuning, moving the cable in various positions and see the result, if nothing happens the problem is not out there. To know if it is some intermittent problem with the FM radio that transmits the signal, the ideal would be to check if other garmin gps has worked correctly. It is also important to test gps and cable separately with different devices.