u/AppropriateHome5724

Hi there, I recently got this (old) Canon F1, which was fully serviced and tested. And everything works perfectly. But there is this noise every time I wind the film. It sounds like it's slipping off the sprockets and doesn't seem to be winding as much as it should. I've tried it with a few different rolls of film, and it has the same problem. With other rolls like Ilford FP4, it has the problem until I wind back a little to "tension" the roll, and then it seems to wind correctly. But if I leave it for a bit, the problem occurs again. Any help or fixes for this?