What was found
(CAN) PILOT REPORTED PROBLEMS WITH ELECTRICAL RELEASE ON CARGO HOOK ASSEMBLY. SUSPENSION ASSEMBLY LATER DISASSEMBLED AND FOUND THAT INNER RING ON SLIP RING ASSEMBLY HAD DISBONDED PREVENTING PROPER CONTACT. THE SLIP RING ASSEMBLY WAS REPLACED WITH NEW PART AND UNIT REASSEMBLED. THE SUSPENSION ASSEMBLY WAS REINSTALLED IN THE AIRCRAFT AND SYSTEMCHECKED SERVICEABLE. THE SLIP RING ASSEMBLY ( THAT IS; DEBONDING AND PITTING) IS A COMMON SOURCE OF PROBLEMS WITH THE SUSPENSION ASSEMBLY.