I have a Whitfield Quest pellet stove. The two speed fan motor causes a 60hz buzzing noise in the control board's relay when it's switched to high speed. It works fine on low speed. High speed also works, it's just that the relay buzzes loudly. I replaced the relays on the control board but that didn't fix it. I need to figure out if the issue is with the high speed circuit on the blower motor or in the control board. My hunch is it's the high speed circuit on the motor. We always ran the motor on high it was never run on low. The control board is $300 and the motor is $100. Any ideas which I should replace first or a way to diagnose this? Anyone experience this problem?