Monkeys in Twilight Princess...?

Basically I'm re-playing Zelda Twilight Princess and I'm really stuck...I'm just going to go and get the Gale Boomerang in the Forest Temple and I know the monkeys are supposed to jump onto the rope and help you swing across, but for some reason they aren't and it's really getting on my nerves!!! I hate these bloody monkeys! Can someone help me???