|Microsoft DirectX 9.0|
The SetDefaultSyncSource method sets the reference clock to the default clock.
Returns an HRESULT value. Possible values include the following:
|VFW_E_NOT_STOPPED||The filter graph is not stopped.|
This method instructs the Filter Graph Manager to choose a reference clock using its default algorithm. For more information about the algorithm that it uses, see Reference Clocks.
Usually you do not need to call this method, because the Filter Graph Manager automatically selects a clock. However, if you call IMediaFilter::SetSyncSource to override the clock, you can use SetDefaultSyncSource to restore the default clock.
This method fails if the filter graph is running or paused.