I do have a virus checker (McAfee) along with Malwarebytes (free version) as well as SuperAntiSpyware (free version) all of which I run regularly.
I think I've found the culprit. I have a laptop which I use as a physical connection (cabled) to the Hub. The setting for 'Updates from more than one place' was set to 'On' along with 'PCs on my local network, and PCs on the internet' being selected. I should have checked it when I checked the computer I use regularly.
I've changed it and I've had no repetition since 29th September. Early days yet though, I had a period from 16th to the 29th when all was quiet.
If that was the cause how does that option work, given that one machine was set to Off and the other, less often used, one was set to On?
In addition to that I'm sure some of the activities were taking place overnight when the only device connected to the Hub that was active (on standby) was the YouView box.
Waking up the system would imply that the system had not shut down wouldn't it? I always go for the shut down option and check that the power indicator light is off. I'm not saying that its not possible that I might not have left it in a sleep/hibernate mode at some stage but not on 6 occasions confined to a 3 week period.
I followed your link but found the options beyond my comprehension. It starts off with 'This topic assumes that you already use and are familiar with Group Policy'. I am not familiar with Group Policy.
The forum describes me as an aspiring expert, which I seem to have earned by seeking lot of help over several years. I'm not an aspiring expert, I'm someone who needs the assistance that this forum can provide. I appreciate the help but sometimes I'm just not able to get my head around it. Don't let that stop you from suggesting it however.
As I said, early days. After a period of normal activity the unusual activity has returned. One day it was the download, the next it was the upload.
The amount of the extra activity seems to be consistent, around 3.8Gb for each (upload/download).
From the device statistics it does not appear to be anything to do with the YouView, and is probably confined to my desktop.
The problem started shortly after I installed the Windows 10 Creators update, about 12 days after. I can't help but suspect that it has something to do with it.