So I am still repairing my Phantom 1 after a pretty severe crash. I have the motors replaced and everything seems to work. I went in to the Assistant software and I see that under the Upgrade section the GPS is listed as version 0.0.0.0. I can't set up IOC or any other settings related to GPS as it says "GPS Needed" in red at the bottom. I don't seem to get satellite lock, and after a bit of flying I get a slow flashing yellow light. However the Phantom is still connected to the transmitter and flies fine for the most part - the only problem is that it will not "hover" in place and overall seems a bit unstable - drifting slowly in one direction rather than sitting still when the sticks are released. I've calibrated the compass and calibrated all the sticks in the Assistant software, and I've checked that everything is plugged in to the Naza correctly. Is there something I am missing here, or something else I can try? If not does anyone have a link to a US seller where I can pick up a replacement GPS unit? Really itching to do some high flying with this thing and get some cool video, but I want to make sure that it is mechanically and electronically sound before I get too risky and lose my copter and my GoPro!