Pixellated pictures on live TV are often the sign of a signal fault. If you've rebooted your box once, then there's likely a fault somewhere, so this will need VM to intervene. You're likely to need an engineer visit, depending on what VM's remote diagnostics turn up.
If only one of your boxes is affected, try swapping them round to see if the fault follows the box move, or remains with the internal cabling. If both are affected, then the problem is likely to be external.
First check the automated faults line for any existing issues in your area that could be the cause: 0800 5610061. If nothing's reported, assume VM don't know about your fault and ideally you'll need to call them.
150 from a VM phone, 0345 4541111 from any other phone - choose the options for "I have a fault with my TV service". Alternatively you can wait on here for staff to respond, which may take a day or so.
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