i replaced the heater resistor because it only worked on the 4 setting. i replaced it but it makes a awful noise from the same region so what could it be? thanks. it gets louder as the setting goes up

I would venture to guess it's the blower motor. Either it's bearing going bad or the fan is out of balance. That is the most logical problem.

If the blower motor starts to fail (the bushings get gummed up) it will draw more current. This will cause the resistor block to fail. If you have to replace the resistor block more than once the blower is the likely cause.