I have been using my Phantom 1 for about 2 mos now without any problems. All of a sudden it will now lose the signal and go into safe mode at around 50 feet. Fresh batteries and still the same problem. It will go through its setup program as usual. Finds the satellites then blinks green. As I get outside of the 50-75 foot range it will start to blink yellow and go into the failsafe mode. I can recover it when it gets inside that range and I turn OFF then ON the GPS switch. Any suggestions as what could have gone wrong? Thanks in advance.