"The lights on your BT Hub indicate different things. It's important to know what the different colours mean."
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Check Your Modem/Router
If your BT Hub is still flashing purple after trying all of the above steps, then it could be due to an issue with your modem or router. C
Check The Test Socket For A Faulty Connection
Is your BT box flashing purple? If so, then it may be due to a faulty connection in the test socket. To check this, unplug all wires from the BT socket and plug them into the test socket instead.
If the light stops flashing after doing this, then there is likely a fault with either your telephone line or wiring. Contact your provider for help in resolving this issue.
Contact BT Support For Assistance
If you’re still having problems with a purple light on your BT Hub and cannot resolve it by following these steps, then contact BT customer support for assistance.