I went and looked at mine and disassembled the paddle release knob. Based on your pictures and mine, I am guessing that my spring is very weak or the brass shaft is not the correct length. I notice your entire brass shaft when assembled is shifted in towards the tub (o-ring showing and knob closer to mixer stand). I can grab my paddle and shift to left very easy. When I am mixing it is very obvious - it starts to make a “tink” sound that progressively gets louder and I had it bind once. My tabs have a rub mark from paddle touching during the “walk”.