My Amp (Yamaha RX V467) has two 'optical in' in AV 1 and AV 4. does that 'optical in' support 5.1? I cannot find that in manual. it say you can connect BD Player through that, so can i assume that Optical in support 5.1 Audio? because all BD has at-least 5.1 surround! so in that case if I purchase a sound card with optical out, will be able to get the 5.1 in in my amp, right?