As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOTH PROPELLERS RPM DROPPED FROM 1050-1020 DURING CLIMB WITH POWER AT 90% TORQUE. IN CRUISE SETTING PROPELLER RPM WOULD NOT DROP BELOW 925 AT 90% TORQUE. CRUISE WITH PROP SYNCHROPHASE ENGAGED PROPELLER RPM CHANGED WITH PLA SETTING. COMPLIED WITH FCD 72-2017-01R1. R & R PCU IAW AMM 61-20-01. OPS & LEAK GOOD IAW AMM 71-00-00. COMPLIED WITH FCD 73-2016-01 AND FCD 53-2016-01.