I think something's wrong with your copy.
I just duplicated your "tests" on my copy of that lens (which I absolutely love, btw - except for baseball games, that's the lens that I default to on what ever body I'm using) - and I wouldn't be happy were I you.
My focus ring is well dampened, but it's dead silent.
And when I shake it - again, silent.
RMA/return it would be my advice.
thanks for taking the time.


























