Slow speeds on some sites

[#1]

I’ve got Fibre Extra unlimited and my broadband connection has been superb for well over a year now.
Just recently in the last 4 weeks, I’ve been experiencing some websites loading extremely slowly. This happens on both my phone and MacBook. I’ve tested switching off the WiFi and onto 4g and the sites load quickly and are responsive.
I have a mesh network Tenda Mw3 (been using it for two years and no issues) I thought it might be this so switched it off and went back to my BThomehub wireless connection (I ditched the plusnet router about two years ago because it was next to useless!).
I’m starting to wonder if it could be interference. The only changes I can think is that the Xbox X has been moved into that room and we’ve bought a new OLed tv.

Anyone got any suggestions?
Is the new Plusnet router any good? I’m just wondering if I should ask for a new router and test that.

[#2]

Which websites? Loading slowly - you mean they take a long time to come up, or actually take a while to fully load?

[#3]

Extremely slow loading like a minute and some just won’t load but try a different website and it loads instantly. I’m wondering now if it is a dns issue. I’ll have another look at the router.

[#4]

Try doing a traceroute to the affected site - it could be a routing issue.

[#5]

What web browser are you using? Safari or something else? If you're using Safari, then have you tried an alternative like Chrome or Firefox?

[#6]

Moderators Note

This topic has been moved from old Fibre board.