Hello everyone, I recently purchased a DJI Phantom 2 Vision which I enjoy a lot. I have taken it out for 3 or 4 flight of about 15 minutes each. Everything was flawless on every flight. I have had the Phantom inside for the past few days and have noticed 2 different potential motor/bearing issues after examining it: First issue: The back right motor on the quadcopter is very "notchy", more so than the other 3 motors. It has much more coarse turns than other 3 as well. There doesn't seem to be much resistance, just more coarse turning. Second issue: The back left motor makes a slight noise when I spin it pretty fast with my hand. The other 3 motors seem virtually silent. When I land the quadcopter, this motor does stop quite a bit sooner as well. There might be a little more resistance on this motor than the others, but not significantly more. Are either of these a problem and if so how should I fix it? Thanks a ton.