Could use some help here before I throw money at this thing. Coin Mech (TRC-6000) wont except coins or dispense change. It just makes a noise but wont dispense or except. I tried three coin mechs, 2 which were newly refurbished and had same issue. Someone told me it was probably the main board and someone else told be it is the bottom power supply board that needs replacing. They both seemed pretty confident. Anybody have an idea?