In the P3 help section some forum members may have read my posts re fitting a Mobius cam to have some audio feedback....well after playing back the last video from the Mobius I could hear an unusual "thrashing" noise from the props. So I put my P3A up to eye level to check the props and sure enough one prop was feathering while the other 3 were smooth. I am changing that prop and will post again when I've completed the next flight. I also now have a tachometer and will check the motor speeds relative to each other whilst idling. These actions are as a result of Adams unfortunate experience just recently. Edit: feathering is the wrong description, better to have said spinning out of true, one blade higher/lower than the other. Sorry for any confusion.