As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MFR-#2 PROP RPM INCRREASED TO 1020 (UNCOMMANDED) FROM 900 CONTROL LEVER SETTING. INCREASED BOTH PROPS TO 1020 THEN RESET TO 900 THEN 850, #2 PROP INCREASED AGAIN TO 1020. FEATHERED #2 PROP. REMOVED AND REPLACED #2 PITCH CONTROL UNIT. OPERATIONAL AND LEAK CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.