A few weeks ago my "Band" button stopped working in the 80 preset position. When I selected the 80 Meter band it just stayed on the band I started from. I can get to 80 by entering a frequency on the keyboard but when I change to another band and then go back to 80 it won't change to 80. Updated to V 2.3.9, same problem. anyone else had this problem? I have a 6400.