Very slow wifi

[#1]

In the past week - our internal wifi has dropped off horribly - it can't maintain three users - just browsing internet - no video...

For one computer to watch iplayer - need to turn all the others off...

This wasn't true last week....

We've two windows 10 computers - they don't appear to be updating / downloading - but I'm struggling to think of anything else.

Is there a way to measure wifi speed - i.e. from router to computer - rather than outside world to router?

[#2]

Download a free wifi analyser app, and check channels in your locality, that are used
by neighbours.
Then choose channels that are not / least used.
Assuming you have dual band router, ensure the SSID's are unique too.
5ghz band currently is far less populated, but has less range than 2.4ghz.

[#3]

channels look ok - neighbours channels aren't very close.  

As far as I can tell - isn't a dual band router - so only have 2.4Ghz available.

The router is white, Sagemcom 2704N model....  We've not been with plusnet all that long - is this an old router?

[#4]

That's what they supply to ADSL clients I believe; another option is to try your old router and reconfigure to PN
settings, to see if that helps. Plenty of Openreach Routers on E Bay; these can be configured to work on PN too.

[#5]

Hey @peter_10,

Thanks for reaching to us here and apologies for the delay in response.

From what you've mentioned it wholly sounds like a WiFi issue, I've performed some testing on the line and there doesn't appear to be any issues. With that being said the advice @Gel's provided is pretty much the troubleshooting steps we'd ask you to take. Please check out this link here and let us know how you get on.

Thanks.