Hi there! I have a Hisense flat screen tv, a Sony blu-ray player, and an older RCA surround sound. The Sony has an hdmi and digital out, the Hisense has all the hook-ups one could need, and the RCA has the red and white audio inputs for tv and vcr, plus a digital audio in. How do I hook all this up to get the surround sound to work? I've tried a few different ways with no luck. Also, I have the blu-ray hooked up to the tv with an hdmi cable. Thank you!