Audio problem: When the Ancient One is explaining to Bruce that taking the Time Stone will affect their reality, there is a shot from behind the Ancient One where she says "Millions will suffer", but her mouth doesn't move when she says the line. (01:24:20)
Audio problem: After Stark escapes, he is walking in the desert, and crests the brow of a sand dune. Then, helicopters burst into view over him and you hear them for the first time. Stark was on the brow of the dune and should have heard them long before.
Audio problem: When one of the computer operators resumed playing Galaga, the sound effect heard is for an enemy ship attempting to capture the player's ship, but what's shown on screen is normal gameplay.
Audio problem: When Happy is talking to Peter in the kitchen at the charity event, from the angle over Happy's shoulder he's talking but the side of his face isn't moving, from that angle we should see his chin move up and down.
Audio problem: At the start of the movie Black Panther gets shoes that are silent when he runs. Half way through the movie when he runs up the spiral ramp you can hear his footsteps. (01:00:00 - 01:01:00)
Audio problem: Near the start of the movie, Darren Cross is showing the Yellowjacket armour to a group of some visitors. One person, named Frank begins talking with Cross about the armour. There is one shot shown during the talk, with the camera behind Frank's shoulder. In the shot, Frank is heard talking but his jaw is not shown moving along with the line.
Audio problem: After Alexander Pierce discovers Nick is alive, Pierce starts explaining the intention of his plan to him. A reverse angle of Pierce is shown where he says "You didn't ask. You just did what had to be done. I can bring order to the lives of seven billion people by sacrificing 20 million." His jaw doesn't seem to be matching up with his speech. (01:42:00)
Audio problem: When the general asks how Blonsky was doing, he doesn't open his mouth. (01:07:40)
Audio problem: Ikaris says by mistake "I am very beautiful" in the local language. Sersi laughs and he asks what did he say. She says "You said..." but Gemma Chan's face is not moving. (00:29:10)