On almost every remote controller the buttons stop reacting after a while, and you end up squeezing the remote out of his life while trying to switch the channel…
I found some link where it explains how to "refresh" the contact-making surface on the backside of the buttons, but that kit is not something I can find around. Could you suggest what would be a good replacement?
I've used aluminum foil with great success before. You can get it from a gum wrapper like Nick T suggested. Just make sure you don't use super glue, it'll dry out the rubber in the buttons and cause even more problems.