ConstThis field shall indicate the duration of the time span to skip backward in the media, in milliseconds. In case the resulting position falls in the middle of a frame, the server shall set the position to the beginning of that frame and set the SampledPosition attribute on the cluster accordingly. If the resultant position falls before the earliest valid position to which a client may seek back to, the position should be set to that earliest valid position. If the SampledPosition attribute is supported it shall be updated on the cluster accordingly.
Input to the MediaPlayback skipBackward command