Looped Flutter Fly (Palloptera muliebris)
Unfortunately, I couldn't get a front view of this fly, but the photo above shows the most distinctive feature of this species, that being the manner in which it holds its equally distinctive marked wings out from the sides of its body.
The body is various shades of brown, the wings have an obvious loop-shaped band on all edges, which are flicked alternatively as it goes about its business. Hence the 'flutter' in its description.
This fly previously came under the name 'Toxonevra muliebris'.

''Toxonevra muliebris'' is a species of flutter fly in the family Pallopteridae. It has been found in Europe and North America. The pattern on the wings of this species is distinctive.