Hi ianmaiden,
Sorry to see you are having major problems with your V6. It's commonly called the green screen of death and will need replacing.
Have you tried signing into Service status at the top of this page and run a test against the V6? By doing this VM should be able to send a signal to your box and try to repair it. It will more than likely fail but should help when calling again as the automated system should recognise you've tried to fix it and hopefully the call will be passed straight through to an agent.
You should try calling 150 again from a Virgin landline, or 0345 454 1111, options 1,1 and 2 (Faults) but best to call at 8am to avoid call queues
You could also 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.
VM Forum Staff may pick this up for you but it could take a couple of days to a week.
Dave
The Service you do for others is the rent you pay for your room here on Earth - Muhammad Ali