I never noticed anything when I had my D80, but then I wasn't a member of NIkonians and I didn't know I might have a problem. WHen I suspected that I might have one, my 18-200 was having focussing issues with the motor and CPU. So when I had those serviced I just sent in the lens. Soon after when I suspected the D7000, I sent in both just to be sure the pair were checked together. Afterthat, they seemed very good together. I dont' have any issues with my Sigma 10-20mm paired with the D7000.