ok since my last post didn't get much response maybe this is of interest to people:
I have succesfully got Cat5 linking a BeoVision 7 and BeoSound 3200 (cat5 in walls, with RJ45 wall sockets, with lexcom RJ45 to Masterlink cables connecting the B&O to the wall)
I get full control and it sounds & works great.
However when I try the same with an active kit it don't work at all :(
Any ideas why? what's the difference between the ML in a TV or Hi-fi and the ML in an active/passive box?