I have one set of Cambridge Megaworks 250D's and I'm so pleased with them I might get another set for my living room. Is it possible to somehow split the RCA cable, hopefully with a box of somekind so I can choose whether to send to signal to the other set of speakers? Also how far could the cable go? I would need probably about 10 to 15 meters to get to the living room. Advice? cheers.