Yes, i strongly suspect someone's got remote access to my system and is scampering about behind the scenes, taking screenshots and getting up to all sorts of mischief. Which is odd, because i thought remote access was disabled.
One thing that may be relevant: some time ago my ISP was BT and i had big problems with my broadband connection, kept repeatedly dropping out after increasingly short intervals. I spoke to BT tech support in India and they told me to turn off the router firewall. I was a bit nervous about the wisdom of this but they assured me the PC firewall would be sufficient on its own, so i went ahead and disabled the router firewall. The connection didn't improve much and some time later i started getting odd reports that my firewall was turned off when it appeared to be on, and that the Avast NDS driver (i think, i'm going from memory and mine is less reliable than many) was failing to load. I did two things - first i dumped BT and got a fibre connection with Virgin Media broadband, second i ran Lenovo One Key Recovery and restored the entire system from the original factory back up discs which i burned when i first got this machine (NOT the stuff on the partition on the hard drive). Before i did this i backed up various files (mostly RAW and JPEG photos) to my two external hard drives. This seemed to do the job for a whils, but i slowly noticed odd little things beginning to happen again; when booting up it would often sound like windows had started (the little chime noise) well before i'd finished putting my password in, web pages would load inexplicably slowly at times despite an apparently good broadband speed and videos and other stuff would sometimes hang for a moment or two, as if a screenshot was being taken.
So, after a while, i came here.
Now, Farbar logs are attached (too long to copy and paste), GMER is next once i've downloaded and run it.
Happy hunting chaps!