Just had my new sony digi-box installed, connected it up to my amp via optical out and....nothing. Well very little. I have to turn the volune control on the amp right round to nearly full to barely hear any thing at all. The amp is also a sony, strdb940. The optical out if connected at the digibox but not the amp shows a red glow so i assume its working. Any body got any ideas? Is it buggered or am I just missing something simple? It works fine via the analogue outputs.