What was found
DESCENDING THROUGH 4,000" ON APPROACH, FAS CALLED AND REPORTED SMELL OF "DIRTY SOCKS" IN THE CABIN ( PACKS A320 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 )--