As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: ON DESCENT DIRTY SOCK ODOR.ON FLIGHT DECK AND CABIN. MAINTENANCE FOUND THE APU FUEL CONTROL UNIT TO APU LUBE MODULE UNIT INTERFACE O-RING LEAKING OIL AND REPLACED IT PER AMM 49-32-11. A SATISFACTORY LEAK / OPERATIONAL CHECK WAS ACCOMPLISHED WITH NO ODORS NOTED.