What was found
FUME EVENT ON DESCENT INTO ATL THROUGH 12,000. F/A STATED THAT THEY SMELLED DIRTY SOCKS THROUGHOUT THE WHOLE CABIN. WE ISOLATED THE PACKS & SUSPECT THAT PACK 2 IS THE ISSUE. ( PACKS WITH MOD 31283/MP P7125 (FWC H2-F1 STND) AND WITH MOD 30626/MP K6443 (ENHANCED ECS) FAULT CAUTIONS ASSOCIATED WITH OPERATIVE SIDE NOT DISPLAYED. PERFORMED DECONTAMINATION OF THE ECS WITH ENGINES IAW AMM 21-00-00-615-003-A. NO ODOR NOTED.