Assembly: PresentationCore (in PresentationCore.dll)
Setting this property tells the MediaPlayer to be clock driven and will utilize the timing engine, placing the player in Clock mode. Any media that is playing is stopped and the Uri associated with the new clock is opened.
When the player is in clock mode, seeking using Position or calling the Play, Pause, or Stop methods will throw an InvalidOperationException. These operations are only available when the player is null.