IAudioLoudness::SetEnabled method

The SetEnabled method enables or disables the loudness control.


HRESULT SetEnabled(
  [in] BOOL    bEnable,
  [in] LPCGUID pguidEventContext


bEnable [in]

The new loudness state. If bEnable is TRUE (nonzero), the method enables loudness. If FALSE, it disables loudness.

pguidEventContext [in]

Context value for the IControlChangeNotify::OnNotify method. This parameter points to an event-context GUID. If the SetEnabled call changes the state of the loudness control, all clients that have registered IControlChangeNotify interfaces with that control receive notifications. In its implementation of the OnNotify method, a client can inspect the event-context GUID to discover whether it or another client is the source of the control-change event. If the caller supplies a NULL pointer for this parameter, the client's notification method receives a NULL context pointer.

Return value

If the method succeeds, it returns S_OK. If it fails, possible return codes include, but are not limited to, the values shown in the following table.

Return codeDescription

Out of memory.



Minimum supported client

Windows Vista [desktop apps only]

Minimum supported server

Windows Server 2008 [desktop apps only]



See also

IAudioLoudness Interface