Additional Control-S port

I have sony vdp-cx850d dvd changer and parasound cdc-1500 carousel cd player. My Control-S port on SLinke v2.3 works perfect with dvd 850d and also with parasound cdc-1500 (through "external remote in" jack there) separately, but when i use "Y" adapter (as recommended for Control-S) and connect two devices simultaneously , sony dvd works and parasound cd doesnot.

Does anybody have an idea of either some additional circuit needed plus to "Y" adapter when using two different producers' devices over existing Control-S port of Slinke, or

maybe someone could recommend me a circuit scheme to add another independent control-S port over parallel port of Slinke please??

Thanks in advance,