Cancelling Buyer Agreement

What is the name of your state? Wisconsin

My husband signed a buyer agency/tenant representation agreement with a real estate agent for a time period of March 11 to June 30, 2005. We worked with the realtor up until a few weeks ago but we are completely unsatisfied with his work and want to find someone else. We tried to send a letter to the realtor, asking him to sign in agreement to change the term date to now so we can move on but he will not (he's being a jerk). Is there any way we can get the agreement cancelled now without having his signature?? Please help!!

unsatisfactory performance

If you can prove that the agent is not performing the tasks that he was signed on to do, the law says that he is in breech of contract and see the contract as unfulfilled, you would not be penalized.