I'm on my 2nd Bugs 5w and I need some help. My 1st one flew great out of the box but after a couple of months it slowly lost control until I could not control it at all. I returned it to Amazon who graciously replaced it with a new one. I've only flown the new on once and I'm concerned it needs some sort of calibration. When using the auto take off, the drone is suppose to climb to about 3m then hover while waiting for you to use the controls to fly it. My 1st Bugs 5w did this perfectly for a month or so then it began drifting upon take off. It also began to land greater and greater distances from the take off point. Then not only did it drift upon take off it deteriorated to the point that it did not accept instructions from the controller at all. I received my 2nd drone a few days ago and on the very 1st flight it drifted backward after auto take off. I was able to fly it and when I use the auto return it landed within a 1 foot of its take off position. I'm beginning to wonder if there is a GPS calibration (not the compass calibration that must be performed every time you insert a new battery) that I need to perform to correct this issue. Can anyone help me?