I have a new P2 and when i Initiate the shutdown procedure (left stick down), the phantom always spins up the left rear (battery side) motor for a couple seconds before turns off all motors. The motor goes to approximately 25% power for a second, but not enough to move the entire phantom. Only this motor spools up. If I start the motors again, they all spin normal. Additionally, when flying "hard,"this same motor is always a tad hotter then the rest, but doesn't burn when touched. Any ideas?