Audio problem: In the original UK VHS release of the movie, during the battle sequence, Spock is lifting a panel on the floor of the bridge and says: "Auxiliary Circuits destroyed Captain." His mouth doesn't move as he's speaking.
Audio problem: After Kronos One is fired upon, Kirk calls down to engineering to ask if they had been firing torpedoes. Scotty responds by looking at the inventory screen and saying "Negative Captain. According to inventory we're still fully loaded." That Scotty sure is fast. He gets through saying "Negative Captain" before his reflection even starts moving its mouth. It's a little dark so turn up the brightness on your screen. (00:28:50)
Audio problem: When Kirk and McCoy enter the underground penal colony, Kirk is confronted by a large beast speaking an alien language. Watch McCoy's mouth when he says, "He's definitely on about something, Jim." His mouth doesn't start moving until the camera shot changes halfway through the sentence. (00:59:45)
Chosen answer: There's a limit as to how much the shields can protect the ship. Depending on the force of the explosions, the ship still suffers some damage from any weapon blasts. Also, the shield only holds for so long and gradually loses it protectiveness with successive attacks, causing increasing damage to the ship.
raywest ★