This is a blind folded shot in the dark, but those having this issue, did you create each orbiter as a child of the core?
I had this problem a long time ago and it was because the obsessive organizer in me decided it would be a good idea to create all my generic orbiters under one generic web device. Visually it looks better in the device tree, unfortunately it doesn't work. The symptoms were exactly the same until it stopped working all together.
Also, unless I misunderstood what was said in the second post, some screens change on all orbiters for a given room. So if you're watching a video in the family room all orbiters for the family room will show the remote screen. You can change any single orbiter to a different screen without affecting the others after the fact, but at the start of the video all orbiters will go to the remote (I think this can be changed in the settings per orbiter.. I THINK).
Edit: This was misleading...(You can change only one orbiter to a different screen without affecting the others after the fact, but at the start of the video all orbiters will go to the remote (I think this can be changed in the settings per orbiter.. I THINK).)