As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT, FLIGHT CREW HEAR LOUD NOISE FROM CARGO AREA WHILE USING FLAPS. MAINTENANCE TROUBLESHOOT AND FOUND THAT THE MOTOR OF THE FLAP UNIT WAS EXTREMELY NOISY. REPLACE FLAP MOTOR UNIT AND NOISE WHEN AWAY. EXPECT THAT BEARING IN UNIT ARE DRY OR INTERNAL GEARS WEARING. RECOMMENDATION AT TIME THIS IS TO CHECK MANUFACTURE PROCESS.