I have a tv, it's not digital, it's analog. I also have a dvd player. I recently bought a surround system and I'm trying to install it with my existing dvd player and tv. Everything is working, however I had to buy a "digital coax" in order to link the dvd player to the surround machine where it's written "digital audio in" and "digital out", is it necessary??? The thing is, I already linked the dvd player with the surround machine using the NORMAL "audio in" and "audio out" connections, and the sound for the surround system works. Should I also link it with the additional digital coax cable through the "digital in" and "digital out" connections? the thing is, wether I link it or not through the DIGITAL connections of the dvd and surround machine using the digital coax, I'm not sure that it's making a difference. Maybe it's not necessary because my tv isn't digital, or the tv has nothing to do with this link between dvd and surround machine? I hope I made sense, please help.