As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: ON ARRIVAL DIRTY SOCK ODOR WAS OBSERVED WHEN APU AIR WAS SELECTED ON. MAINTENANCE FOUND THE EMERGENCY GENERATOR HAD A HYDRAULIC LINE LOOSE AND LEAKING (AALA202308313246). MAINTENANCE ALSO FOUND THE BRAKE AUTOMATICE SELECTOR HAD A HYDRAULIC LINE LOOSE AND LEAKING. (AALA202308319139) MAINTENANCE TIGHTENED BOTH HYDRAULIC LINES AND CLEANED THE APU INLET PLENUM AS EQUIED. A SATISFACTORY LEAK / OPERATIONAL CHECK WAS ACCOMPLISHED.