I dont think you can just do sound from the core, plus you would have to worry about getting the audio/video to sync. I have a similar set up to what you are talking about -kind of. My core is a headless unit in my server closet, its audio output is connected to a receiver that powers my ceiling speakers throughout my house and on my back patio. I wanted to put an LCD on my back patio that used those patio speakers that were running off of my core. Instead of worrying about putting a MD on my patio and playing the movie on both the MD and my core, I just cut a VGA cable open and soldered some Cat6 in between connectors, ran that 50ft cat6 from the core to the back patio, and just connected it to my LCD screen. (basically it is just a 50ft VGA cable). Works like a charm for me. I tested to see how far I could go with it and it seemed that 50ft was good but at 100ft I started to get some pretty bad signal loss.