As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - WHILE TAXIING TO PARKING, THE NR 2 ENGINE FEATHERED, THEN CAME OUT OF FEATHER WITHOUT ANY INPUT FROM THE CREW. THE POWER LEVER WAS SLIGHTLY AFT OF THE FLIGHT IDLE GATE. THE CONDITION LEVER WAS AT MIN. REPLACED NR 2 PROPELLER CONTROL UNIT (PCU). RIGGED PCU AND PERFORMED ENGINE RUN. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.