Our youngest electronics fanatic loves buttons and switches. It makes me crazy on days when he gets a hold of any remote or "works on" any set of control buttons.
Some friends had this same problem with their young geek who flitted around their tv controls like a moth to flame. As the tv must remain in its present location, they had to find a something to prevent their wee technophile from the on/off and channel buttons.
With pure hacker ingenuity they broke the prongs off two electric outlet covers and duct taped them over the raised buttons. Voila! Mini-AV geek foiled!