Not registering arm movements - xbox

I have tried to do the 9 week program, but I cannot even get through one workout because it will not register movements on any of the arm activities. It will track my arm movements if I move them around, but will not register when I do the exercise. It tells me to follow the trainer, but she does not do anything. At times, the trainer does move her arms, but it still doesn't work. I've made sure that I wait until she tells me to go. Any other suggestions? I am so frustrated!! I love Active for wii, but this one is about to go on ebay.