Weird Output Problem...

Roadhog 4
External Keyboard
External Mouse

Been running the same show file on the same show for 2 days. Tonight, we started experiencing something that I'm having a hard time describing but I'm going to try.

Sitting in a cue (houselights) for over an hour
No one sitting at the console
No other playbacks running
No clock timers running
Fader 1 Cue 1 is up and running
All fixtures in the cuelist drop to 0 intensity.
Output window shows 0 intensity (and view sources says it's being controlled from the Houselight list)
Hit "VIEW CUE" - Values are stored at 100%
If I select the fixtures and hit TOUCH - they come up 0 %
If I hit "assert" or "Go Cue 1" - fixtures come back up.