It is one of the three bulb rear projection screen models. Last time, I heard that dust in the unit could cause overheating, so tomorrow, I will take the covers off and blow it out with compressed air.
Is this a common thing with you Toshiba owners? Does it indicate overheating because of dust, or maybe it needs new bulbs? I'll dig for the instructions tomorrow, but would appreciate any input you might have in the meantime.