Something odd about this.
The TiVo has 2 power-saving options, the only difference between them is the timer. One is a 2hour limit, the other is 4. And in either case, the onscreen message you describe appears for a couple of minutes before the box just goes into power-saving and the video output is disabled.
I presume you've restarted your TiVo recently, just to eliminate the software feeling a little queezy? (technical term)
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