My reciever is capable of decoding both DD ETX and DTS ES (discrete and matrix). My DVD player is rated to decode both DTS and Dolby digital. The problem is when I have a disc that supports DTS ES discrete, the reciever will not recognize the digital encoding. If I switch it back (through the DVD menu) to standard 5.1, then the reciever picks up the encoding and will play in ETX. I was under the impression that a DTS encoder was a DTS encoder and it didn't necessairly have to be a DTS ES DVD player. So is it my DVD player causing the issue, a setting within my reciever or my method of connecting them together (oprital)?