Hi, I use the Goapp and Map Pilot all the time and fly out a large area with a M100 and always with a near 100% connection, I think your right in saying it could be your controller or it could be on the other end to. A couple of years ago I built a s900 with a e1200 upgrade and A3pro, and exactly the same thing was happening to me, this thing didnt have a rth function just came back after loss of connection. Igot so fed up with that I decided to dismantle the thing and soon found the problem, it was one of the antena extension cables that push into the LB2 that had shaved on the pinch point almost cut in half, when the legs raise and lower. I had no idea and completely out of sight, replaced and fixed. sometimes the problem is staring you in the face,