You are not the only 1's i live in marske TS11 area and to have the same problem i have not had a very good connection since i upgraded to 50meg 4 weeks ago but since last week have had this strange problem.
After spending a few days changing routers abd cables and connections only to still have the same fault, finally rand virgin and got hung up on twice(1 scottish guy asked if my connection was through a router i said yes its in your router u supplyed he said we dont help if its through a router it will be your equipment thats faulty and hung up)
i had 2 engineers round for 4 hours yesterday finlly said they did not have a clue what was causing it and never seen the fault before and left going to ring me on friday to see if its fixed it's self.....:-(
the only way i can view most pages including this forum is through there proxy server....webcache.virginmedia.com:8080
Thanks virginmedia