Facing TV Problems? Ask a TV Technician.
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Honestly there are only three things that could cause this- your Mainboard (least likely), your HDMI cable (somewhat likely) or your Cable box simply needs to be replaced (most likely). The Charter tech has no way of knowing the box is "fine" internally, besides the fact that perhaps it was working when he left. But if you've had the mainboard replaced this many times- I have to ask- what ELSE have you tried on the TV besides this cable box?
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