Fisher & Paykel Model DD603 Top drawer makes grinding noise while running.

Most likely the rotor is either damaged or there is some debris sitting in the rotor cavity.

Follow the instructions in the user guide to lift the filter plate. Then twist the collar that holds the rotor to free it up. Lift the rotor out carefully and check for debris in the rotor cavity.

Also see if there is any debris in the drain sump next to the rotor cavity. Take a thin rigid wire and clear the channel between the rotor cavity and the drain sump.

If rotor looks damaged you will have to replace it. Costs about $50.

Let me know how you go with this.