Audio problem: When the Woads attack in the beginning of the movie, after the knights have pretty much won the day, Bors hold up his fist knives, sticks out his tounge, and yells a sort-of war victory yell which sounds rather comedic. At the end of the movie when the knights and their horses charge into the Saxons out of the fog, you can hear Bors' exact same yell once again.
Audio problem: When the Woads are surrounding Arthur and his knights, one of the knight is shouting something, but nothing comes out of his mouth.
Audio problem: In the ice battle scene, after the Knights unsuccessfully attempt to make the Saxon army cluster to break the ice, Arthur tells the Knights "It's not going to break". But if you look at Arthur, his lips aren't moving when he says it.
Answer: I don't think it's supposed to be German. Probably Old Saxon. Could be something like "slahten fiand" - slaughter enemy.