I have just bought a new Smart HD 3D TV and instead of purchasing a soundbar -I was hoping my current Surround Sound 5.1 would work. Previously I had connected my bluray via an optical lead to the surround sound and also the audio red and white cables plugged in to the receiver and into the TV - and it worked when playing a film etc. now it doesn't work and I have done the same connections. I don't know what to do..Do I need to buy a sound bar and amp? My surround sound system is a good one but is over 7 years old - please help?