Strange problem. I have an option 11 with 2 cabinets and a pri. The 2nd cabinet has clicking problems with outside calls but only the outside caller can hear the clicking not the person on the pbx. The only card in the cabinet that’s having these problems is the digital line card, the other cards in the cabinet are analogue and do not seem to be experiencing the same problems. I’ve tried to isolate the problem by switching the card to another slot but the problem follows. I also tried removing the amphenol and putting a set on it with no other sets on the card, problem still persists. Is this a fiber receiver problem or what am I missing here.