Audio problem: During the ambush of the British troop, as some of the soldiers take their first aim, it cuts to some Hurons running downhill. If you look in the lower left corner of the screen you can see a Huron firing without us hearing it. (00:17:35)
Audio problem: Shortly before jumping through the waterfall, Hawkeye says to Cora, "If we go there's a chance there won't be a fight." However, if you watch Hawkeye's mouth, the audio doesn't match his lip movements.
Audio problem: When Magua complains to the Marquis about not getting his revenge after Colonel Munro's surrender, the Marquis' lips don't match the audio whenever he says Magua's name.
Answer: Major Hayward is supporting one of the soldiers as they enter the cave. After they make their way down the rocks, he puts the soldier down on the ground. The other soldier appears to be killed by one of Magua's gang.