As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
VERY LOW AIRFLOW FROM BOTH PACKS. BORESCOPED ALL COCKPIT GASPER DUCTS FOR BLOCKAGE OR BROKEN DUCTS FOR APPROX 6FT, NO ISSUES NOTED. FOUND BOTH RECIRC FILTERS SEVERLY CLOGGED, PICS TAKEN. INCREASED AIRFLOW IN COCKPIT NOTICED AFTER FILTERS REPLACED. CLEANED SENSOR FILTERS.