Is the IS mechanism and is the sound normal? Not nearly as noticeable on the camera (5d Mark iii). I chatted with a tech with B & H Photo and he says it is normal on the IS lenses. The only one I have to compare to is the 70 - 200 2.8 L IS USM. and I can't here it at all on that one. He said it was due to the much thicker and metal casing.
Can any other owners of this lens let me know if I need to exchange it.