Every Nikon with a ruberized finish (4) I own has developed this problem. It is an epidemic among most of the late model cameras from all manufacturers that have this type of finish with no cure and no means of prevention. It seems to be almost entirely related to age, as cameras stored in cool environments in benign atmospheres (including with dessicants) often develop it. It is a major bummer which is forcing me to consider getting rid of a lot of cameras I thought I would be using 20 years from now.