Good theory, but mine will do it whether I just turned it on or it's been on for hours.
Now, I still have the same DVD player (Sony). The optical cable is not the culprit because when I started using coax for the DVD, I switched the Monster Cable to the Dish on opt2 and it works fine.
This is something I should have pursued early on, but I didn't. My workaround suits me fine though. (don't use opt1) Maybe when I get a new DVD player, I'll try it again.
Todd