Its either the Guinea fowl or the chickens and Im pretty sure its not the chickens. Ive never seen a stray rooster with our mob either. I need to find out what it is, its got me so curious and thus thinking it may be the Guinea (named Vinny).
I have one Male Guinea fowl and 3 chickens and I hear crowing of a morning. We used to have a rooster, but not now. He maybe mimicking the rooster. There is no other explanation.