My problem sorted.
I have a HP laptop. I looked at Task Manager with no apps running. I found 7% to 15% of CPU usage being taken all the time by
HP Touchpoint Analytics.
A web search showed several sites with people's complaints. Basically, it's a HP "spyware" taking off data to improve security and customer experience
It is not clear whether this was just a HP update, or whether MS accepted it into their WIN FALL update.
A big moan is that you are not asked to agree to data sucked off.
Well - I uninstalled it.
Will watch to see they do not try to sneak it back on again.
So far, so good.
Pete.