I have done some more looking around, and have found that the companion program to Vegas, namely DVD Architect Pro, will provide correct surround sound placement, so in conjunction with the 5 channel multi-meters within Vegas (on the right hand side), it is possible to get close enough. What is not possible without further hardware, is hearing the surround sound in real time through Vegas. Apparently an external device is needed for the processing. On the SONY forum, it was described as the "Asus Xonar U1 external USB sound card; it encodes Dolby Digital Live to its optical output." (
http://www.sonycreativesoftware.com/Forums/ShowMessage....) So actually nothing to do with the wiring or optical output. Problem solved, or at least, question answered.