Pixellation is the result of poor TV signal, which is often the result of a fault. Any streaming app on your TV box is carried over the internet and so wouldn't be affected by this. And Freeview is a different platform to Virgin, it uses terrestrial transmitters & aerials, whereas Virgin is a cable-based platform.
You can try calling 0800 5610061 to see if it's a reported area fault, otherwise you will need to report it yourself. At this stage, you have 3 options for contacting Virgin..
1: Use the text message service (07533 051809) this can take a few days.
2: Wait on here for VM staff to respond, currently around a week.
3: Call TV Faults and be patient & persistent. Perhaps try calling earlier in the day.
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