This may a problem with either your V6 or a signal issue. Have you got another VM box to switch over and check if it has the same issue?
Have you made sure that all coaxial connections are snug and tight?
Is the issue with 5HD or 5 SD?
If it's CH5 HD and the following channels are also breaking up then it's probably a signal issues if you've done the checks above.
Film 4 HD, S4C HD, Sky History 2 HD, S4C HD, Sky Sports F1, Sky Sports NFL HD and Star Plus HD.
If it's CH 5 SD then you need to check the following channels Talking Pictures, 5 Select, 5 USA +1, 5 USA, 5 Star, CBS Drama, More 4, E4, E4+1. If they show the same issue then it's a signal issue. In which case you need a tech visit, otherwise it's a replacement box.
Either way you need to contact the Faults team.
You could try the text messaging service. Just send a text with a description of TV Faults to 07533 051809. Your message will go into a queue and a representative will respond to you as soon as possible.It may take a few days.
You can also call 150 from a Virgin landline, or 0345 454 1111, options 1,1 and 2 (Faults) butbest to call at 8am to avoid call queues
When calling Faults you will go through a series of questions/tests, if that doesn't resolve the problem then call back around 10 minutes later and an agent should pick the phone up.
The Service you do for others is the rent you pay for your room here on Earth - Muhammad Ali