i built a new quad (after several successful quads with Arducopter 3.x) - its a F450 with Sunnysky 2212X motors and 10x4.7 props and simonK 30A ESCs, running a 3S pack.
this quad flys great on stabilize after auto tune, nice and quiet and smooth.
but as soon as i flip ALT HOLD on, it starts jumping up and down slightly (i can hear the motors "popping" all the time).
i tried some tuning but nothing really changed it. once i go back to stabilize its stable and quiet one more time.
im attaching a log of the last flight where this is shown.
can you advise what to do?