What was found
WE HEARD A LOUD BANG IN FLIGHT AT THE TOP OF DESCENT. THE SAME NOISE OCCURRED SEVERAL MORE TIMES AT THE BEGINNING OF EACH DESCENT. UPON INSPECTION AFTER LANDING, THE DEMI CAN IN POSITION 7D WAS NOT PROPERLY SECURED AND IT WAS SLIDING BACK AND FORTH DURING FLIGHT. WE LANDED UNEVENTFULLY. IAW AMM: 25-57-00-1-2 AMM: 25-57-01-4 AMM: 25-52-00-6 VISUAL INSPECTION OF MAIN DECK CARGO COMPARTMENT AT POSITION 6D AND 7D. NO DAMAGE NOTED ON FLOOR TRACK AND CARGO HANDLING COMPONENTS. SIDEWALL LINERS ALSO HAS NO DAMAGE. OPS CHECK OF LOCKS FOUND SATIS. AFFECTED CONTAINER AND ADJACENT CONTAINERS HAVE NO DAMAGE. ACFT OK FOR SERVICE.