We have to switch our DVD player on then select the specific output from that to get it to play TV movies etc in surround sound. (on ours it means pressing the 'source' button on the remote) We have no extra cables other than the ones that came with the package and allow us to watch DVDs.

Have you tried searching for a forum or help page on the internet to see if someone out there has the answer. Try typing the make of your tv followed by forums and see what turns up.

Kenny