JohnDuncan:When you say 'blanked', don't you mean it has a little swing-in built-in cover instead of a plug in nipple-y kind of removable cover like they used to have... EDIT - certainly looks like it from photos. If you push an optical cable into that 'blanked' socket, the cover should swing out of the way.
Yes! But the socket looks like the squarey shaped connector that you run from a printer to a PC (with a USB at the other end). The dealer lent me a cable that has a circular shaped connector at each end with a pin like thing inside, whatvere it was it didn't look like it would fit, so I didnt try to insert it, matron. Now I know that's the right hole, I'll see if union can be made....