As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) HARTZELL PROPELLER INSTALLED AS PER STC #SA685AL. TROUBLESHOT VIBRATION SINCE INSTALLATION. INSTALLED SECOND PROP AND DID DYNAMIC BALANCE, THIS CHANGED THE POSITION OF VIBRATION. REMOVED PROP AND INSTALLED ZERO TIME MCCAULEY PROP. VIBRATION GONE.