I find that whilst my drone is hovering it tends to descend slowly. Never left it high and see how it drops but I do notice when I am bringing it into land I leave it around 10 feet in the air and it slowly descends. I also notice that as I land it often 'bounces' comes down and as I get close to touch down it always gives a bounce up again. Is this just prop downdraft hitting the ground or the sensors underneath? Both? Just curious. Compass. IMU both recently calibrated.