I try to leave it on for few min on a slower speed but still the same thing. When I move the speed all the way up it seems like one side lifts up much faster then the other and then it flips on one side. When I manually spin the propellers with the finger it feels little bit tight but they all move, its kind of bumpy but they all move though. Its just not lifting up, its just keep flipping on the same side....It may be that one side propellers are moving faster then the other. I have tried re-calibrating, resetting, changing mode, put the new batteries but same results....Also I am not sure if the signal on the remote controller should always be blinking or is it an indicator of something. Thanks.