Missing frequencies on FM transmitter?

 

On my StreetPilot 2730, there are three or four ranges of frequencies that are skipped whenever I try to match the FM transmitter to the radio station. For example, if I set my car radio to 104.7 (an open station in my area), and then try to set the FM transmitter to 104.7, it skips from 104.5 to 105.3. Does anyone else have this problem?