Pixellation tends to mean you have a fault with your TV signal, a reboot is a sensible precaution once, but if that's failed to resolve then the underlying fault needs resolving. And no, your TV channels aren't carried over the internet so your router doesn't get involved.
You can try checking for area faults on 0800 5610061, but if nothings' reported - then VM don't know about your issue and you're best reporting it.
150 from a VM landline, 0345 4541111 from any other phone, is the best way. VM staff respond on here, but it's currently taking upto a week.
In the meantime, and out of interest, is it C4-SD or C4-HD that's affected?
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