I got a 1996 Chevy truck with the same problem.

Are you talking about the blower motor resistor block? If so, a lot of times the connector overheats and it damages the terminals so you need to replace the resistor block and the pigtail for it. You also need to measure the current that the blower motor is drawing. If you have a 30amp fuse, the motor current should be under 20 amps on high speed. If it is higher than that, you need to replace the blower motor too. Its also a good idea to inspect the connections at the HVAC control head for overheating.

Same problem with what, the radio?