As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FUME EVENT DURING CRUISE FWD F/A'S CALLED TO SAY THEY SMELLED A DIRTY SOCK SMELL. AFTER TRYING TO ISOLATE F/O SAID HE COULD SMELL IT IN COCKPIT AS WELL. PERFORMED ISOLATION OF RECENT CABIN ODOR, IAW TSM 05-50-00-810-831-A. USED APU BLEED AND ENGINE BLEED AS SOURCE OF AIR. PERFORMED ENGINE IDLE RUN, IAW AMM 71-00-00 NO ODOR REPRODUCED. AIRCRAFT OK FOR SERVICE.