OK, thanks all... think we have cracked it.
I think the issue was that kaspersky confuses Steam running as "you are playing a game" and so stops the normal update process.
I never have steam staring with my PC, but I have been playing a game that means I dip into the game every 2 hours.. so I have tended to leave steam running.
I have changed it so that "game mode" is not selected as an option (and ensured steam is exited) and sure enough... recently, kaspersky has been doing the update process every 2 hours.
So Kaspersky should fix it.. such that game mode is only effective when you are genuinely playing a game..
But at least we seem to have a workaround. I would like to have "game mode" active for when I am genuinely playing a game... since now.. it might do an update when I am really playing a game (prob not a real issue.. my PC has enough grunt that it probably wont matter)..but for now.. having it disabled is the better option.
Thanks to everyone for their help.
Just to close this out.. Kaspersky support did get back to me, with the response of
"We received a response from our experts stating that the unwanted notification is already addressed. We suggest reinstalling the application as follows and letting us know the result."
May be I am being cynical, but that sounds to me like "we have no idea.. just reinstall"..
We will see... as I said, that member of the family is away from home.. so may take a while to get to them to fix..
But I am sure a reinstall will fix (though it should not be necessary).
