It could be signal related, possibly. Do you have the same issue at all times of the day?
You can check to see if there are any reported service issues in your area using this link: http://my.virginmedia.com/faults/service-status If it's not an area fault then the system will perform a few tests of your installation to see if there's anything obvious.
The show is pretty unwatchable it's an expensive monthly cost for something that doesn't work. Could a virgin representative contact me if no one else has any ideas? It's stuttering glitching pixelating.