If the buttons of your game are not reacting properly or not working at all, try this (at your own risk ) ):

Carefully open the game and make sure no parts are falling out. Clean the inside of the rubber buttons and their surface where they make contact.
Make sure you do this cleaning process very carefully. Do not use any strong cleaner, in many cases a liquid soft cleaner or a contact spray for electronic parts is working.

Before closing the game, check if all parts are at their right place. Make sure you close the game nice and tight, but don't 'overdrill' the screws.

If you've never opened a G&W game so far, first try it on a 'old' game or on a game which is broken, before you start this process on your valuable games!

- Patrick