As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INSPECTION TYPE:N/A LOUD HIGH PITCHED SQUEAL AT CRUISE FL 330. LOUDER IN SUPERNUMERARY AREA. SQUEAL NOISE REDUCED FL 350. BUT STILL OCCURRED. CHECKED FWD CREW SEALS REF AMM 52-10-18 NO DEFECTS NOTED CLEANED SEAL PRESSURIZED ACFT IN REF TO AMM 05-56-00 CHK'D FOR LEAKS NO LEAKS OR NOISE NOTED IN SUPERNUMERARY AREA ALSO CHKS GOOD.