Had Sky+ installed yesterday. Hooked up the optical output to my Denon 3801 amp, enabled DD output on the Sky+ box but haven't yet had a DD5.1 signal. Tried all the movie channels last night and not a squeak! I have double checked that the DD setting on the Sky+ box is correct and the amp is locking onto a digital signal but the DD5.1 signal doesn't seem to be there, only PCM. Any help appreciated.