You are still using the Euro software, are you? There is one station in the US which is preparing to broadcast TMC messages (forgot the name of the station but it got mentioned here somewhere as well). The RNS-E has a dual tuner, one is always looking in the background for a better RDS frequence and a station which broadcasts TMC.
In theory it would be possible that your RNS-E picked up some test packets of a future TMC service. If this is true this would another reason to stay with the Euro software and a patched US map...
In theory it would be possible that your RNS-E picked up some test packets of a future TMC service. If this is true this would another reason to stay with the Euro software and a patched US map...