Stop action in view when uinavigationcontroller clicked back to previous view on iPhone

I have a uinavigationcontroller with 2 views. In the second view I have some audio playing. When I click the back navigation item on the navigation bar the audi开发者_Go百科o still plays. How do I end the process of anything happening in the second view when the user clicks back to the initial view.

Thanks for your help.

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Use the 2nd view's viewWillDisappear method to stop the music