My Phantom 3 Standard has an issue with the video signal. I use my OnePlus 2. My first several flights were alright and I got some decent live video range. Then it started losing the video signal after I took off. I could still control the drone and the gimbal, just didn't have a live feed. It only reconnected at about 3 meters above the ground. I recalibrated the IMU and that helped for a couple of flights, but the problem came back. IMU calibration stopped helping. Most of the times the video feed didn't work, although it was alright in some places. Sometimes it worked but for the very limited range. I turned off the video cache, and generally tried many solutions from the forum, though none of them seemed to help. I also tried using iPhone 6S, which seemed to work slightly better, but definitely not as it supposed to be.