Pixellation on live TV - assuming you've rebooted your box once - is a classic symptom of signal issues somewhere. It could be a fault in the box itself, it could be a a problem in a connection, or maybe in some cabling between your home & the streetcab. In anycase - that's for (with a couple of caveats) VM to identify once you've reported it.
W02 - as per error code help - is a "loss of signal" error, the next step after a pixellation issue gets worse. At the risk of stating the obvious - any faults agent may say there's nothing wrong with your cabling or box, but something clearly is - did you point this out, and if so - what was their response?
If you're able to check any of the following channels that you also have access to - Animal Planet HD, More4-HD, Sky Documentaries HD, Sky Cinema Thriller HD, Sky Sports PL or Football HD - do these have any issues?
Ultimately - you'll need to report the issue to VM and be a little insistent, that you have a fault, you're not calling up for the fun of it, and VM need to take the appropriate action. In your case, this will likely be an engineer appointment. If you get nowhere with this avenue, VM staff will respond on here - but it may take a few days given that it's now the weekend.
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