Hi.
First question here-have you done a wired speed test? Wifi channel changes aren't going to do anything if the line speed is poor. Checking over ethernet with just one device connected, and everything else off will show you your line speed.
If wired speed is fine, then wifi is the issue. Have you also gone through most of the channels, maybe using a wifi analyser app to track down the best channels for you? Also, which router a re you using?
If the wired speed is still low, then you're possibly looking at a line fault, and you'll want to clear the in home checks to make sure it's not your end.
First, check if the line is quiet. Call 17070 from a landline phone, pick option 2 for the quiet line test, and listen for any noise there. If it is, you have a phone fault. Do the test socket test below, but with just the phone connected and with a spare handset if possible.
Next, connect to your test socket, by removing the front plate of your master socket (there's a guide on this forum-just google plusnet test socket guide if you need help). Retest your broadband speed wired here with just the router connected. If speed here is good, the problem is inside somewhere, and you want to build back to normal set up bit by bit to find where the speed drops again. If it's still poor in the test socket, report a fault at faults.plus.net so they can start testing and get the engineers out if needed.
