Kitchen aid professional 600?
The part that attaches to the paddle, whisk, dough hook keeps falling down. And, when it is pushed back on it no longer turns. But, when you take the mixer apart and this part is not attached it does turn. The gears all look fine. It was recently taken in for repair. And, work fora short time before the one part started falling off the body of the mixer.
Robin, February 2016