What was found
(AIRCRAFT NOT GROUNDED) DESCENDING THROUGH 28,500 FEET F/A'S REPORTED STRONG DIRTY SOCK ODOR. WE FOLLOWED THE QRH SUPPLEMENTAL PROCEDURE AND THE ODOR DEMINISHED GREATLY WITH PACK 1 OFF. FOUND APU FCU LEAKING. REMOVED AND REPLACED APU FCU IAW AMM 49-32-11-000-003-A AND 49-32-11-400-003-A. OPS CHECK GOOD. ITEM: 1C/W TC 21-000-002. FOUND APU FCU LEAKING. REMOVED AND REPLACED APU FCU IAW AMM 49-32-11-000-003-A AND 49-32-11-400-003-A. OPS CHECK GOOD.ITEM: 1C/W TC 21-000-002. FOUND APU FCU LEAKING. REMOVED AND REPLACED APU FCU IAW AMM 49-32-11-000-003-A AND 49-32-11-400-003-A. OPS CHECK GOOD.