The bl-ray player is a Sony BDP-S7200 which has a red 3.5mm female socket with DIGITAL OUT COAXIAL PCM/DTS/DOLBY DIGITAL marked on it. The only other sockets are USB, HDMI out and Lan (100).
Thank you or your advise. As I am awaiting delivery of my projector I am unable to do as you advise but it appears to be the logical solution. Perhaps I can come back to you if it dos't solve the issue in a couple of weeks time.
Very many thanks, R