My SR4200 receiver has an 'RC-5' remote control socket (really just a normal phono socket) and my Marantz CD player also has similar remote control input (and output) sockets. They're both coloured orange. The SR4200 manual says it "allows system remote control to operate". Does anyone know what this does? The SR4200 comes with a universal remote which controls my CD player just fine. I connected up the RC-5 sockets with a phono lead but this didn't make any difference (I don't really know what difference it could make!). Anyone else used these remote connections and know what they do? Michael.