My guess would be that the cabling is RG 6 in a 7 year old house, but you certainly should check all connections to make sure they are tight.
Pixelation is usually (or at least frequently) a sign that the signal strength is too low at the STB.
Is this a new install, or has it been working ok for a while and suddenly the pixelation showed up? If it is new and has never worked right, I would go look to see if you can find an attenuator somewhere in the cabling. Actually, even with an old install that could be the problem. I recently experienced severe pixelation on a number of HD channels, have had FiOS TV for over 3 years, never had the problem before. Everything checked out remotely from the FSC, but when the tech came to the house, he found a 6db attenuator attached to the back of my DVR; it had apparently been there from the initial install, never gave me problems until this past week, and suddenly it did. All he had to do was remove the attenuator and all was fine again. He had no idea why the attenuator was even there, or why it suddenly started causing problems.
An attenuator could be anywhere in your cabling, at the ONT, at the splitter, behind the wall outlet, or at the STB, you may have to do some searching to see if that might be the problem.
Of course, since the pixelation is bad, Verizon should be willing to send a tech out to the house to fix it, at no charge.
Verizon FiOS TV, Internet, and phone
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