Terrain is checked not to show inside model

I've rebuilt the terrain and it's still showing inside the model. What am I missing?

I closed the plan then reopened it and the terrain was not showing inside. I have no clue to what's going on. I rebuilt the terrain a number of times before and it made no difference. I saw another thread from a few days ago and it sounded like they were having the same problem. Maybe X6 was having a "bad day". :)