First flight of the day goes fine, and if I land the Phantom, shut down the motors and restart them, everything works fine. But if I power cycle the Phantom to change the battery (or for any other reason), the Phantom has electrical power but a CSC won't start the motors. This occurs with both my batteries, so it's not a defective battery--and again, note that the Phantom has electrical power, acquires nine or ten satellites, operates its camera, and is generally fully functional except that its motors won't start. Once the Phantom rests for a considerable period of time, maybe fifteen or twenty minutes or longer (I haven't experimented fully), when it's then powered up, a CSC will start the motors. My power cycle procedure is to power down the Phantom, then the RC unit, then the range extender, and to power them up in the reverse order, all per the User Manual. I function in Naza-M mode, though I can't imagine that would make any difference. Heat seems the most likely reason, but the Phantom doesn't seem warm, and it happens even in mild ambient temperature after just a ten-minute flight. If anyone has any ideas or suggestions, I'd appreciate them.