Took the wheel apart and to my surprise everything looked good. Teeth on planetary gears were perfect, no cracks, no wear on any of the teeth, plenty lubed. Turned freely, no resistance. So I have no idea what's going on. Only makes the noise at full throttle or when it's on PA5. Doesn't slip or have any loss of power just makes that awful noise. Also only makes the noise when on the bike under weight.