Clicking sound in right rear interior panel with ignition turned on

It is probably the motor/actuator that controls the damper for air flow to the overhead or floor outlets (look on overhead console for button). Turn off the rear A/C and see if it stops. Switch between floor and overhead mode and see what it does. I just disconnected mine and now it only blows overhead. To disconnect just remove the tray on top of the passenger side rear panel over the rear A/C. There is a connector near the front that goes to the damper.

Replace the blend door actuator. thats the offender