Audio problem: In the beginning of the film, when Trudy offers her son more cereal, her mouth doesn't move as she speaks. (00:01:45)
Audio problem: Carly leaves the voice mail message for Paige and the whole scene with the truck gets on the voice mail. When Blake checks his phone after the music stops, the message isn't the same as earlier. (00:48:00 - 01:09:45)
Audio problem: When Vincent is trying to stab Paige in the warehouse, he slashes her foot and she falls down. As he's trying to stab her through the metal grate, she's screaming but her mouth is closed.
Answer: It is simply a contraption to keep Wade in place so he doesn't move and the wax can be applied. It's also used to keep the wax out of his eyes, ears, nose and mouth.