I don't rule out it could be something in the content, so you should always test other movies with the same audio output format to see if the problem exists with a particular format. Your description indicates you did that, but I'd check others with the same format and then check settings in all relevant equipment. You might consider deleting and redownloading that movie as well, it might not change anything, but it's easy to do. What you describe can happen, but that's a large difference in volume between the movies. If you identify the movies involved others can test for the problem as well (including me).
If inconsistencies remain, my first recommendation in all of these cases where there is inconsistent playback in audio (or video) is to first determine which component in the chain might be responsible for the issue by isolating components one at a time. Start with the simplest removal, in this case the matrix. Bypass it by going straight to the Denon and see if the problem is still present at playback. If no change, you'd want to remove the Denon as well, but obviously to do this you need a display with audio, or another Receiver or Processor. If the problem persists, then check the Strato to determine if it's causing the problem (setting or otherwise). (NOTE: I actually do this as a first step if I suspect the problem could be in the Strato, but it usually is not.) You do this by connecting the Strato directly to the display (or a display), and replay the content to see if the problem persists. I realize this isn't always doable, especially in a projection system, but it does allow you to test what you are describing because if the audio volume is consistent between the movies when the Strato is directly connected, then the problem is elsewhere in the setup.
That second paragraph might be a lot of work, so obviously start with the content tests and replacement, and rechecking all settings before removing equipment. You might also wait for feedback from others to see if it's something in the audio coding that we are all experiencing.
Jim
