Quoting the RCgroups page: http://www.rcgroups.com/forums/showthre ... 32&page=51 I had no problem up to 1660 feet overhead, but I just checked my Vision + transmitter in the RC assistant software and it was set to CE...even though the pot is set to FCC and the transmitter beeps twice on start up...everyone should check the software. I changed the radio button to FCC and turned off and on the transmitter and the FCC button stay lit... I checked it out too. 2 beeps on power up. When I downloaded the RC System Assistant Software 1.1 from DJI and connected my transmitter to the computer (USB port on bottom), the radio button DID say CE mode. I clicked FCC mode and powered off/reconnected and now the software keeps the FCC radio button. Have to go take a look and see if it made any difference. See for yourself...interesting at least.