I've seen this bug in my room a few times this summer, never been able to get a good picture of it but I'm hoping my description can provide some clues.
It has a dark, ant-shaped body and black, nearly opaque wings that stay upright like a wasps rather than folding against its body like a beetle. The wings are sort of narrow with bulbous ends. It's quite capable of flight. It's about an inch long, maybe a bit smaller. The first time I saw it was, I think, in June. I'm not sure what else to say about it but if you have any questions I'll do my best to answer.