only been the last few weeks and its very intermittent, it could be something to do with going back to yosemite or something I've got installed.
basically once in a week or so ill notice that 3 or 4 times in an evening, my screen will flash momentarily black, like it would do if the resolution changed, or if someone logged in with team viewer (they haven't). and maybe it'll then happen a few minutes later.
it just happened twice, id lots of apps open, so i restarted, and hadn't opened anything except steam which opens automatically, and it did it again.
basically once in a week or so ill notice that 3 or 4 times in an evening, my screen will flash momentarily black, like it would do if the resolution changed, or if someone logged in with team viewer (they haven't). and maybe it'll then happen a few minutes later.
it just happened twice, id lots of apps open, so i restarted, and hadn't opened anything except steam which opens automatically, and it did it again.