Can you clean the switches with a Q-tip and some alcohol?
Or lightly sand them?
On our TV, the channel control is a rocker switch. Push left to make the channels go down, one at a time, push right to make them go up. It is a real pain. Most of the time we switch channels through the satellite receiver, which has only an on/off switch on the unit, and all of its other functions are on the remote.
I've heard that other equipment, such as computers and stuff, needs to be used occasionally or it will cease to function.
Can you get to the INSIDE of where the switches are, and get a "contact cleaner" type spray inside of the switch itself? If so, it MAY help things.