In reply to Ben_Climber:
> We have tried the master socket in both other ports and the engineer has said that there is nothing coming out of the port. Hence why he left it at port 1 and told me there must be a wiring issue between port 1 and 2/3.
> An electrician has since tested the wiring and confirmed its all fine.
> Confused!
I don't know anything really about this except though DIY - when I originally set up an internet connection, all I did was connect an extension phone wire into the back of the master socket. Never moved the latter. Ran the extension cable behind the wall, across the attic and down the wall where I wanted the pc. Installed a normal phone surface plate. The router is just plugged into that extension socket via a filter.
If your router does not work then maybe it is your wiring of the extensions that is the problem? Don't think you want to shift the master socket to one of the extension points if that is what you were trying.
As two others have suggested though, a wifi extender or power line extenders is a great way forward. Ironically, my master is in the lounge, but I don't use that and have the router on an extension in another room, and now use extenders via the power line to take internet back to the lounge for the tv! Also have a wifi extender to boost wifi through the house. All works well.
BTW as you have BT tv they will sell you power line extenders for something like £20 and these allow two Ethernet connections so you could say have a pc hard wired at your tv. Or add another and have it elsewhere in the house - anywhere you have a power socket.