One of many useful features that comes with IIS Media Services 4.0 and Smooth Streaming is the ability to stream live and on-demand content with multiple language audio tracks that are selectable by the viewer. An example of this capability is the recent schedule of events that Vatican Radio ( http://www.radiovaticana.org/ ) delivered during the last month.
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Multi-language audio with IIS Smooth Streaming: An example from Radiovaticana Live Streaming