It should not be a gpu issue i'm running a 1080 you might be right it might be a Maya LT issue
I would normally ask you to send me the scene file but i can't open Maya LT files here, hopefully someone might come along that knows more about Stingray PBS than me.
if you do find the answer let me know i'm curious now.
Sorry could not be of more help
David
From a readers' Q and A column in TV GUIDE: "If we get involved in a nuclear war, would the electromagnetic pulses from exploding bombs damage my videotapes?"