As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB THRU FL 296 WITH 7.6 PSI CREW HEARD AUDIBLE AIR LEAK SQUEAL WHICH CONTINUED THROUGHOUT CLIMB TO FL 320 & 7.9 PSI. ACFT RETURNED WITH NO EMER DECLARED & LANDED WITHOUT INCIDENT. SQUEAL COMMENCED DURING RETURN & DESCENT UNTIL APPROX 14000 FT & 6.4 PSI. SQUEAL WAS EXCESSIVELY LOUD & INTERRUPTED COMMUNICATIONS. R & R FIRST OFFICERS WINDSHIELD IAW AMM 56-11-11.