As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HIGH PITCHED WHISTLING SOUND EITHER COMING FROM THE FIRST OFFICERS SIDE COCKPIT WINDOW OR WINDSHIELD. WAS LOUD ABOVE 30K FT, STOPPED DURING DESCENT BELOW 24K FT, SAME AIRSPEED AT ALL ALTITUDES. THE AIRCRAFT WAS GROUNDED. REPLACED FIRST OFFICERS SLIDING WINDOW AND LEAKED CHECKED IAW AMM 56-12-00.