As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE AIRCRAFT WAS GROUNDED. LIGHT DIRTY SOCK ODOR IN CABIN LASTING 5-10 MINUTES WHILE IN CLOUDS DURING DESCENT. ACCOMPLISHED CABIN AIR QUALITY JOB CARD 26L00021001. AUXILIARY POWER UNIT PLENUM WET WITH OIL WITH OIL STREAKS FOUND AT 6 O'CLOCK POSITION ON TURBINE BELLMOUTH PER TSM 21-00-00-810-801A. APU REPLACEMENT REQUIRED. REMOVED AND REPLACED APU PER JOB CARD 26L31049005. OPERATIONAL CHECK GOOD.