I had this same problem, they sent me a new box but the problem persisted. They eventually sent an engineer who changed a cable
on the back and fiddled around. The problem is back again, I just don't know what do do next!
I've moved your post to a new thread, keeps things simpler!
Most faults are resolved after one attempt, but sometimes there may be multiple issues causing pixellation - or perhaps a recurrence of an original fault. Reboot your box once to be sure.
The answer is the same - call Virgin and report the fault. Check on 0800 5610061 that there's no known issues already, otherwise call 150 and choose the options for "I have a fault with my TV service"
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