Hi, my gps started to do some problems:
In GPS flight mode the LED flashes one time green and 3 reds, and the quad wont hover in point but drifting.
So I think my GPS is broken and buy a new one.. and steel the same problem!! 3 red flash and drifting in GPS mode.
All of this after check connections and compass calibration.
What can I do?
Thanks,Daniel.

Your GPS signal it very weak. Try to fly in the opened and wide space