What was found
CREW REPORTS CAPTAIN`S POSITION COMMS THROUGH O2 MASK INOPERATIVE. FOUND CONNECTOR FOR COMMS LEAD AT CAPTAIN`S O2 MASK POSITION FAULTY. SWAPPED CAPTAIN`S O2 MASK RECEPTICLE WITH 2ND OBS POSITION. CAPTAIN`S POSITION TESTED AS PER MM AND NOW OPERATES NORMALLY WITH COMMS AND OXYGEN. LEAK TEST CARRIED OUT OK. 2ND OBS POSITION IS NOW DEFERRED INOPERATIVE FOR COMMS AND O2. REPLACED BOX ASSY. OPS CHECKED GOOD PER AMM.