Audio problem: Watch and listen when Marion is being held prisoner in Nepal by one of the thugs. As he seizes her, she's grunting in strain/pain. We can see this in the first, frontal shot of them. However, in the following side shot (from slightly behind Marion as Toht walks over with the heated poker), Marion's mouth is completely still and almost shut, yet her sounds continue (and these sounds would have to be made with wide-spread lips).
Audio problem: At the beginning of the film, one of the guides goes to shoot Indy with a gun, but as Indy uses the whip to defend himself, the gun bounces off a rock and goes into the water. As the gun hits the rock you hear the sound of the gun firing, but there is no sign of a flash from the barrel or any gun smoke. (00:03:10)
Audio problem: When Toht walks in with Dietrich and Gobler, watch the background, you will see Dietrich's lips moving, but you cannot hear him saying anything.