can happen if the wrong washers are in there (not thick enough) but hard to say just from the pic. They look right, but you might be best off doing some measurements I think. Measure the thickness of the washers, etc. If you can source another CAS (cheap second hand one might be best) and put it in the car then turn it over by hand slowly and listen to see if it rubs it might tell you a bit more. I'd order a new seal and washers, not that expensive.Then see if it still hits