My P4P+ has elevation stability problems. Tell it go up and let go of the lever it keeps going up. You put down input into it and hold it . It will stop but not stable at one height. Put down into it and it will start down slow then speed up so fast it will show maximum motor speed on the scene almost doing a control fall. You have to put up into it to get it to slow down to land. It is acting like the GPS is not telling it it's height above ground. Any idea's out there?