Hi Timbo,
I believe its a sync issue. Others have commented on this before. Denon seem to have acknowledged as such with various upgrades to the firmware. It not bad, very brief silences (fraction of a second) maybe once or twice in a film and it doesn't always happen now. DTS, DVD audio or SACD haven't ever exhibited problem and its a lot better since the last firmware (E) change over my original version in the player (5 I think). DD is fine via the spdif and it was always an option if it annoyed me. Firmware upgrades are scary, especially the 3 disc B version to enable sacd on the denon link

Just praying not to large expensive doorstop at the end of it