As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HIGH PITCHED SQUEAL IN COCKPIT IN CRUISE. SOUNDS LIKE F/O SIDE WINDSHIELD TOP OR RIGHT EDGE. MAINT TEXT: TALKED TO CREW UPON ARRIVAL. THEY SAID IT WAS A VERY HIGH PITCH SQUEAL FROM THE FRONT WINDSHIELD. WHICH REQUIRED WEARING EARPLUGS DURING FLIGHT. REPLACED F/O WINDSHIELD.