Check your wiring and set-up - double socket

If you're having trouble with your broadband connection there are a few simple checks that could fix the problem straight away, saving you from having to call us. They might also help you avoid paying any unnecessary engineer call-out changes.

If you have Fibre to the Home, have a look at Fibre to the Home: Check your wiring and set-up for information.

Otherwise, follow these steps if your master socket has two sockets, like this:

Check your wiring and setup

Step 1: Check your phone line is working properly

Problems with your phone line can affect your broadband, so start by checking it's working properly. Plug a phone straight into your master socket and listen for a dial tone. If there's no dial tone or the line is noisy, you can fix landline problems and report a fault by logging in to our troubleshooter or by using the My BT app on your smartphone.

Step 2: Hub check

Check all cables are firmly plugged in. The broadband cable (grey ends) must be plugged into your Hub and the other end into the master socket. Make sure the power cable is connected to your Hub and the power socket.

Check your wiring and setup

Check that the Hub is switched on and the lights are steady blue. For more help see: What do the lights on the BT Hub mean >

Step 3: Master socket check

You must always plug your Hub into the broadband connection on your master socket. If you plug it into a phone socket or extension, it just won't work.

You don't need microfilters - not for your Hub or any other devices connected to phone sockets or extensions.

Step 4: Set up rules and scenarios

  • Avoid using extension cables for your Hub as they may cause problems with your connection. If you must use one, then use a new, high quality broadband ADSL extension cable
  • To connect more than one device to your phone line, you'll need a splitter. The splitter must connect to the phone part of the master socket
  • If you're trying to connect a BT TV box, this connects via Ethernet to your BT Hub. Find out more about setting up BT TV >
  • Some other TV services need a phone line, in which case the TV box must connect to the phone part of your master socket. Please refer to your user guide or TV service provider for help

Click on the drop down to see images of common setup scenario.


Common home set-up scenarios

Scenario 1: Simple set-up when your phone and Hub can both be near your master phone socket.

Simple microfilter set-up


Scenario 2: Set-up where the phone is connected near the master socket and the Hub is located further away using an ADSL extension cable. Remember - using extension cables can affect your connection.

Microfilter set-up with extension sockets


Scenario 3: Set-up where the phone and the Hub are located far away from the master socket.

Microfilter set-up with Hub on extension lead


Scenario 4: Scenario showing how to connect a third party set top box that needs a phone connection. The TV box connects to the phone part of the microfilter via a splitter. The phone connects to the other port of the splitter.

Microfilter set-up with phone on extension lead


If your broadband connection problems seem down to your internal wiring, you can get a local electrician in to check your wiring. Or, we can come and sort it out for you for a Charge.

Please ask for details of openreach engineer charges