Question about the PS2 game The Chronicles of Narnia: Prince Caspian?

Okay, so I just got the game yesterday and I am on the part called Miraz Castle ault, where I need to lower the drawbridge with Reepicheep and Trumpkin [sp] the dwarf. So I am at the part where I need to pull down the four levers so they will all be down, but it is taking an awefully long time. They keep raising one way or another, no matter how long I keep at it. Is there some sort of trick to this part that I'm not getting? Or do you think my game is simple defective? Help is so much appreciated!