Never had a massive problem with the speed (even if we never had very fast internet but it was ok), but for the past couple of days, the speed has been decreasing massively. We are not even reaching 1Mbps! I can barely search on Google, listen to music, and don’t even try loading a YouTube video !
I have reset the router, try to check the speed and indeed it is very poor. Both the WiFi speed is slow and when plugged in via Ethernet cable.
On checking the line, we can see that the line was 'banded', or capped to 567Kbps due to instability. I've now removed this banding but my tests aren't revealing the cause of it and so we're going to need to look at a spot of troubleshooting to determine whether the issue is internal to your premises or an external line fault.
And if that doesn't help the next thing would be to rule your internal wiring out by plugging the connection into your test socket which is under the faceplate of your master socket and seeing if the instability and speed issues abate. This rules out internal wiring, face plates and extension sockets as being the cause. How to locate the test socket and set your connection into it can be found here.
If the problem still persists from here we will go down the route of raising a fault and getting an engineer out to investigate further.