NEW member here! But I just found this thread after getting my spanking new 24-70mm f2.8ii from Amazon. I immediately noticed the "Tick Tick Tick" sound while zooming both from 24 to 70 and back. It one of the newer batches with the new CENTER PINCH lens caps. It seems to catch at regular intervals which leads credence to someone here mentioning that it is some kind of sensor/brush that relays focal length data to the camera.
The lens is otherwise just great optically. There doesn't seem to be many forum threads on the Internet regarding this issue. I wonder if folks are simply not hearing it or if it is a rare occurrence.
Has folks been able to swap out for non clicking ones that are of recent production? I got the lens at the recent price drop and love it. Thanks for all your help, folks!
I got mine exchanged at the beginning of June for a pre 2013 build after my discovery of the clicking/ticking sound on previous copy I had. Not sure what the options are now really. I'd of hoped that it would be sorted out by now with new copies but maybe not. I also find it strange that there's not more talk of the issue. I guess some have better hearing than others or maybe it doesn't bother other people. Certainly would bug me though. I've still no idea as well why it only appeared from 2013 copies onwards. They must have changed something I guess. Maybe it doesn't do it with all of them too. Could be to do with how tight the zoom ring has been adjusted etc.