I've managed to resolve the issue. While using the TP Link utility I could see there was an extra unknown device connected to one of the Powerline devices. Using the TP Link utility I removed the...

I've had the device for less than 1 year and it's been working fine, but over the last 10 days it has started to impact my WiFi signal. When the TP link is switched on I get poor Wi-Fi, for example...