iphone 7 plus faulty home button

Can anyone assist with a problem with a faulty home button. Holding it down I can feel it trembling and hear a slight rumble and the widgets zoom in and out on the home screen goes in and out of focus?

This is as if there is a bad contact on the button? Could this be an ingress of water or a faulty chip?

I have tried resets but that does not work. Any suggestions please.