As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ODOR IN THE CABIN-FD. DUE TO HISTORY OF ODOR IN THE CABIN-FD. REPLACED TORN BELLOW ON FLEXIBLE SURGE DUCT. REF AMM FOR VALVE REMOVED AND REPLACED. REMOVED APU SOV & INSPECTED UPSTREAM & DOWNSTREAM OF VALVE. NO OIL CONTAMINATION NOTED, DUCT CLEAN. RE-INSTALLED APU SOV.