I think the issue is with the spacing between the inputs and outputs on the 990, not the diameter of the Outlaw(or other manufactures) PCA interconnects. As you have pointed out Gonk, a good number of locking RCA's from other manufactures are virtually the same diameter as the outlaw cables. To clarify my post above I was referring to the RCA outputs from the 990 to the 7125 (running a full 7.1 system it is very cramped!). Really by design the spacing does not accommodate the locking connectors adequately. That said it’s a minor inconvenience in my opinion, the 990 is an outstanding Pre-pro.