https://www.istore.co.za/power-adapter-extenstion-cable
I bought the extension cable. It stops the vibrating.
I've owned over 20 laptops and this is the first time I've had vibrating laptops. Both my Pro and and Air. This is clearly an Apple design flaw.
iStore staff said the cable is...
Many of the stores are out of stock of it.
Guess some people are aware of the vibrating problem and buying the 3pin.
This is ridiculous from Apple. I'm going to report it and hopefully Apple products will be removed from stores.