Best thing for yellow 1200 cases is strip it down.
Remove the LED's
Put in a dishwasher on a pan wash with a Finish "RED" powerball tablet.
Comes out like its 1992 :-P :-P :-P :-P
Same with yellowed keys.
takes a couple of washes.
Put the keys in the cuttlery tray and put some tin foil over the top with, held in place with an elastic band. Its stops the jet blasting the keys all over the inside of the dishwasher.
IT WORKS :-D :-D :-D