As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
COCKPIT FWD WINDSHIELD ANTI-FOGGING AIR VERY LOUD. NO OBSTRUCTIONS NOTED. NOISE DECREASES WITH RT RECIRC FAN OFF. ACCOMPLISHED SVC TIP MM 21-22-00, OP CK OF NOISE LEVEL OK. REPLACED RT CABIN AIR RECIRCULATION FAN IAW MM, OPS CHECK OK. NOISE WITHIN LIMITS.