Under 17th edition every circuit should be rcd protected unless it is for a specific circuit and protected by metallic earthed capping or conduit (this could be a possibility to bear in mind as a last resort).
If your house were a workplace, taking the earth out would be illegal under regulation 8 of the electricity at work regulations 1989, so I certainly wouldn't recommend that!
I would start off by disconnecting everything to do with this (including the broadband cable) except the new tv and the virgin box, both powered from the same socket.
If the rcd still trips you will know the problem is to do with one of these, if it doesn't then start reconnecting the equipment as it was until it does trip, then you will know what is causing the problem.
Adam
June 2009