As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TROUBLE SHOOTING FOR A REPORTED "WHINE" NOISE WHEN N1 IS ABOVE 71%, A FIELD BORESCOPE INSPECTION DISCOVERED A MISSING 3RD STAGE IP ROTOR BLADE. DISASSEMBLY OF THE ENGINE CONFIRMED THAT ONE OF THE 3RD STAGE IPC ROTOR BLADES WAS MISSING.