I have my Internet wired through my house via the wall sockets. Basically my internet signal goes from my computer into a gismo in the nearest wall socket which means that I can connect to the internet via any electrical socket in the house which works fine except for in the extension. I have tried every socket in the extension and it will not connect, if I run an extension lead from the main house to the computer in the extension it works fine. It used to work but not any more. The extension is fed from the same supply as the main house but has it's own sub-meter. Any ideas ??