As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: ON DOWNWIND CLT AT 6000" 190 KNOTS DIRTY SOCKS SMELL NOTED. GOT BETTER AFTER TURNING OFF LEFT PACK . FLIGHT ATTENDANTS SAID IT WAS FAINT SMELL IN CABIN. MAINTENANCE ISOLATED THE SOURCE OF THE ODOR TO THE APU. **SUPPLEMENTAL REPORT WILL BE SUBMITTED** (OPEN)