Perhaps update your 3808's firmware?
I have a co-worker who has just recently (finally) purchased a BluRay player. He also happens to use a Denon 3808 and he's bitstreaming from the BR player (Sony BDP-S570).
He was just mentioning a few days ago that he had lip-sync and audio dropout problems when playing the DTS-HD audio from the "A-Team" BluRay. He asked if I had any ideas. I told him to check the firmware on the S570 and the 3808. Just today he told me that he checked both last night; the S570 was up-to-date, the 3808 wasn't. So he updated the 3808, and he says it seems to have fixed the problem. No idea if it was a fluke, or if the 3808's F/W really was the culprit.
So, perhaps check on your 3808's firmware?
