Audio problem: In the drug dealer's attic, when he shoots a rat, there is a very long echo - as there would be outside - for example in a forest. But inside, the echo would be much, much shorter. (00:43:25)
Audio problem: The sound is off when Marcus and Mike are in the video store talking about "The Box". It's most visible during the over the shoulder shot of Mike miming putting the word "flaccid" in the box. Mike's mouth is CLEARLY not in sync with the words that you hear. (00:56:35)
Audio problem: In the shoot out in Tapia's new home, one of the Americans is shooting a MP5SD at the men on the balcony, but the weapon sounds like an M4. (02:09:05)
Audio problem: In the scene where Mike and Marcus are in the pink house, Marcus says "you got to call yourself the devil in his house?" his mouth doesn't match what he's saying.
Answer: He was looking through a tiny mirror he was holding in his hand.