Weekend weird dropouts and speed issues

[#1]

First noticed my Sonos radio stream drop in and out (pretty annoying, like every minute or so) but assumed an issue with Sonos.

Then noticed that some web connections to popular sites were taking a long time to connect, or timing out.

Rebooted router, naturally,

Issues remain - and when I did a broadbandspeedcheck, got 32Mb/s reported as download... but 0.13Mb/s as upload, with 18ms ping. So, assume that stuff is coming down ok, but any transmission in the opposite direction is stymied.

This is second day of this - any ideas?

Thanks

[#2]

I've had ongoing issues for months, I'm trying everything and calling plusnet everyday, also had 3 engineer home visits with no resolve, just doing know what to do anymore, might have to relocate WiFi router to different part of the house