What was found
RDU - FLT 0360 - EN ROUTE DFW/RDU DURING CRUISE, SLIGHT SMOKE NOTED IN CABIN WITH NO OTHER ABNORMAL INDICATIONS. AIRCRAFT PROCEEDED TO RDU AND LANDED WITHOUT INCIDENT. CHECK OF AIRCRAFT REVEALED STA 950 TO STA 950A LT CABIN AIR SUPPLY DUCT RUPTURED. AIRCRAFT MAINTENANCE FERRY RDU/DFW. REPLACED STA 950 TO STA 950A LT CABIN AIR SUPPLY DUCT. SYSTEM GROUND CHECKED, NORMAL OPERATION. (X)