I have been having to calibrate sticks everytime i fly lately and on the left stick i have trouble calibrating right and left turning. When calibrating left turning on left stick it will not go to 100%. I was able to calibrate sticks today but when flying after about five minutes I could not turn right or left, hit the RTH and it came home fine. Am flying in mode 2, firmware is up to date, and no error messages everything is normal. I am thinking a bad left stick. Anyone have similar problem?