Visible crew/equipment: Episode 22, Season 5 - "Vessel": Lex returns to the mansion, after being abducted, with his new powers. When he shows Lana by shooting his hand, they start talking by the stained glass window. The reflections in their eyes are supposed to be the light coming through the window, but are actually from a white screen used for lighting. The reflections in their eyes are rectangular to confirm this.
Continuity mistake: In Episode 22- Season 5 - "Vessel": At the start, Lex wakes up and heads towards an open field many miles away from the mansion. They show a camera shot of his face in the field and the sky is grey and cloudy, but in the very next shot the sky has turned blue and the sun is shining.
Audio problem: At the beginning, you hear the horses braying and the dog barking, but you can tell none of the animals are making those sounds. The sounds were added in afterwards.
Answer: No, there is no such character in the comics. He's a "meteor-freak" like all the other baddies on the show. The sound has something to do with him vibrating his vocal cords very fast to create a high-pitched squeal.