As with most processor controlled powered on devices (those with standby power circuits) the 976 will supply about 5V to the microprocessor chip. The power transformer is only energized, when it's powered on by the processor.
Therefore, there should be no regulated voltage to result in heat radiation in standby. If you're experiencing this amount of heat in standby, definitely something wrong. My 976 measures about 95° when powered on, and cools off quite quickly within a couple of minutes.
I have it on a shelf with all open sides.
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