If you mean a Beolink active 1611 with "active kit" you will have the same problem, because your problem is not a BS5 problem, it`s a Powerlink problem, and BL active also uses Powerlink. What you would need is a little device that opens the audio outputs of BS5s Powerlink sockets after a delay, triggered by PL PIN 4 (5 V). I`m not a technician, so I couldn`t do that, but I think Ulf is the man. www. ulf-kiener.de
He is a Beoworld member too, mainly active in the german forum.
BTW: Is your Naim amp a power amp or is a preamp included. I`m asking, because PL outs do not send fixed line level signal, so if you crank up your BS5, it may be too much for the Naim`s input...(?)
Stefan