HI PAUL, I HAVE NOT COME UP WITH A SOLUTION TO THIS PROBLEM, I THINK IT'S AS
YOURSELF AND OTHERS HAVE SAID, YOU HAVE TO PUT UP WITH IT.
I THINK PUTTING AN ELASTIC BAND ROUND IT WILL ONLY CAUSE MORE PROBLEMS,
AS YOU WOULD HAVE TO KEEP MOVING IT ALL THE TIME, WHEN CHANGING FOCAL LENGTH.
EVEN ASKING NIKON TO TIGHTEN UP, AS I THINK DABHAND SUGGESTED, WOULD ONLY
SOLVE THE PROBLEM SHORT TERM, AS IT IS BOUND TO LOOSEN UP AGAIN AFTER A WHILE.
BEST OF LUCK WITH IT. IN THE MEANTIME JUST ENJOY USING THE LENS.