Thanks to all for the replies..To answer a few queries, yes I hit 6 channel bypass on the remote, my understanding is this is the only way to access the 6 channel functionality, correct?

I have checked all my DVD audio settings (Pioneer DVD-563A) and it doesn't have a very robust change list, unfortunately not the answer.

Like I said, this has worked in the past, for both of these SACDs, that is the most frustrating part!