Like someone else said, it is simply due to worn eyelets/bushings. It will not cause a stuck stab.
A long time ago, I heard it was was caused by a vibrating elevator, due to the stabilizer trim providing no load on elevator, hence if there is any freedoom in the setup, it can vibrate a bit.
I thought Airbus had changed the setup, a changing the stabilizer setting to provide a bit of load on the elevator, but perhaps not, since I had the same problem a couple of months ago.
Under all circumstances, it is a known problem, but doesn't seem to be something to be overly concerned about, although it is annoying.