Facing TV Problems? Ask a TV Technician.
Hello, Are you viewing your cable programming from a Box- and is that box connected with an HDMI cable?
If so, that is the most common and likely cause of this problem, since the commercials are being processed in the cable box, and are of a higher magnitude in signal. You would first want to replace the HDMI cable and if the issue persists beyond that the cable/SAT box would need to be swapped- as it's sending excessive DC from it's HDMI port.
The reason this points more towards the "Source" than the TV, is that you mentioned it occurs during a commercial- the TV does not know the difference between a movie, a broadcast or a commercial, but the cable/SAT box does process each of these signals a bit differently and would be the culprit causing the TV to shut off.
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