What was found
FLT 2292, MIA-JFK. ODOR IN COCKPIT DURING DESCENT . MUSTY DRY SMELL COMING FROM AIR VENTS . HAPPENED TWICE AT FL 230 & 13,000 WHILE ENGINES WERE GOING TO IDLE; MX ACTION CARRIED OUT PER TASK CARD A 2117101-03. DID NOT SMELL ODOR IN COCKPIT. INSPECTED PACK DUCTS AS OUTLINED IN TSAK CARD A2117101-03. NO OIL FOUND. REPLACED R/H RECIRC FILTER PRECAUTIONARY . NOTE : ON COCKPIT ODOR REPORT PILOT INBOUND ITEM COMPLAINT OF DRY SMELL NOT OIL ODOR.