What was found
ATL/FLL - FLT 131 - ON DESCENT, UNABLE TO CONTROL PRESSURIZATION IN MANUAL AND AUTO MODE; CABIN PASSENGER OXYGEN MASKS DROPPED. CABIN CLIMB INDICATOR FOLLOWED IVSI. INSPECTED AIR CONDTION DUCTING AND NO DEFECTS NOTED. PERFORMED PRESSURIZATION USING MANUAL MODE; OPS CHECKED NORMAL. REPACKED PASSENGER CABIN OXYGEN MASKS AND ASSIGNED MEL. SUBSEQUENTLY, PRESSURE CONTROLLER WAS REPLACED AND MEL REMOVED. (X)