Throughout the movie you can see the microphone at the top of the screen. You think if they can afford actors like Diane Lane and Richard Gere, then they can afford a good editor!
It is totally appropriate that the comment about the microphones seen in the movie Unfaithful ended up on Slipups.com, for the comment in itself is a total mistake.
The copy of the film viewed by the one who complained about the microphones was an illegal copy -- i.e., a copy that was never intended for viewing by the public. It was a copy of the completed movie BEFORE the finishing touches were made. No major motion picture, of course, is ever released with multiple instances of microphones appearing at the top of the screen, so, as far as I can see, someone saw a pirated version of the movie and then complained about it. What a slip-up!
Actually, a LOT of movies get released with that kind of error. That's why slipups.com EXISTS!
I don't know about his slipup being factual, but your dismissal is definitely without merit.