Every summer we get invaded with these tiny tiny little black flies that are about 2mm. They cover the windows and even get inside the double glazing. We have to shut all the windows and curtains. Some make their way in the house and get everywhere. They are all over the pc the walls windows, its drives us mad.
No one seems to know what they are all about. Im quite near to farmland and have asked my neighbours if they all suffer the same fate and they do but not as bad.
Its usually July, August time they appear and it lasts for about 3 weeks.