WPF UserControl still active after Viewbox Child switch

I have a viewbox and an initial child usercontrol that displays a webbrowser. If I open pandora or youtube and begin play开发者_开发问答ing audio and the click a button to switch the viewbox child to a new user control, visually it changes but I can still hear the audio in the background.

Any suggestions?

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The same behavior (audio playing for Pandora or YouTube) is true for tabbed browsers as well. The web site owners consider it a feature to continue playing the audio.

Since you cannot change their implementation, the only option you have is to dispose of the web control, or navigate to a different URL (say about:blank) to unload the web page (which will stop the audio).