I have a BTHub6 (running 19.7.18 firmware) on Infinity 1. I suddenly started having problems streaming radio and TV to devices that had worked fine previously. Standard browsing was difficult and Amazon devices reported difficulty connecting to the Internet. The OOKLA Speedtest app as used by BT Engineers) reported download speeds of 0.05Mb/s and similar for upload. Under normal circumstances I'd det 17Mb/s and 1Mb/s respectively. Sometimes I'd get periods of uninterupted high speed and then suddenly it would go slow again.
The ever useful BT Helpdesk said the fix was to separate the 2.4 and 5 MHz bands. On being told this was already the case the solution suddenly became the reverse. This of course didn't help neither did reboots. Sometimes after an instant reboot or leaving the hub off for 20 mins I'd go back to 17Mb/s but by the time I'd run another Speedtest I was back at 0.05Mb/s. India helpfully told me the problem was my microwave, but nothing had changed in my environment. At least they booked me an engineer with a 4 day delay and nothing else of use. Trying to diagnose an issue on a laptop with 0.05 download speeds was no a quick and simple thing coupled with the myriad of issues that BT Broadband and hub users seem to experience. There is no escalation path from the BT helpdesk and they won't / can't monitor a line or run traces.
With the line running, but hopelessly slowly I felt that BT might be throttling my line, but BT claims not to do this. I started switching off devices and running tests and the one that seemed to be causing issues was my Windows 10 laptop. Task Manager and Resource Monitor were showing little activity other than MS OneDrive sending to -0011.dc-msedge.net (no doubt the MS Azure cloud centre for OneDrive storage). Why OneDrive was synching was something of a mystery as no new data was due to pass, but it seems W10 and OneDrive can swamp the Hub6 certainly with the latest firmware. OneDrive and the same directories have been in use for > 1 year on the same machine. The hub should be able to protect itself at some level. OneDrive has a networking option where up/down speeds can be limited and I have done this (25 Kb/s) and this seems to protect the hub and allow normal Internet usage again. I doubt the scheduled engineer would have worked this out and might have initiated a fight over whether the problem was mine or BTs via the hub and tried to bill me a callout charge.
I can't be the only W10 (2.4 Ghz) and OneDrive user (and I backup little) and BT encourages cloud usage.