As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DMI 545540 - STRONG SOCK SMELL FROM APU BLEED AIR ( APU BLEED AIR SUPPLY SYSTEM (APU AIR NOT AVAILABLE; WILL NEED GRND AIR CON AND AIR START CART) ). GROUNDED - YES. REMOVED AND REPLACED AUXILIARY POWER UNIT, S/N: P-1400, PER T/C 330-49-HWI-02. OPERATIONAL CHECK & LEAK CHECK WAS GOOD. NO FURTHER DEFECTS NOTED. PLACARD REMOVED. MIC SHEET UPDATED. A/C IS OK FOR SVC.