Rinse Cycle on Washing Machie Won't Start?

It's a Hitachi PAF-820P and every other cycle works fine, including the spin so I know it's not the motor, but for some reason when it gets to the rinse cycle a loud buzzing noise starts to come from around the left side of the control panel. I tried fiddling with the settings and a bit and it doesn't matter what it's set to the noise still occurs, any ideas how to fix it would be appreciated.