What was found
AIRCRAFT WAS GROUNDED: ENROUTE: UNCOMMANDED EVAC HORN MULTIPLE TIMES. FLIGHT CREW FOLLOWED QRH RESET INTERMITTENT PA INOPERATIVE, INTERMITTENT CABIN-FLIGHT DECK INTERPHONE INOPERATIVE, INTERMITTENT CABIN INTERPHONE INOPERATIVE, DRAINS FOR GALLEY AND BATHROOMS FROZE, DID NOT DRAIN UNTIL AFTER WARMER AIR. MAINTENANCE FOUND #1 CIDS DIRECTOR FAULTED AND REPLACED IT PER AMM 23-73-34. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED.