The MM_MIXM_CONTROL_CHANGE message is sent by a mixer device to notify an application that the state of a control associated with an audio line has changed. The application should refresh its display and cached values for the specified control.
MM_MIXM_CONTROL_CHANGE wParam = (WPARAM) hMixer lParam = (LPARAM) dwControlID
Handle to the mixer device (HMIXER) that sent the notification message.
Control identifier for the mixer control that has changed state. This identifier is the same as the dwControlID member of the MIXERCONTROL structure returned by the mixerGetLineControls function.
An application must open a mixer device and specify a callback window to receive the MM_MIXM_CONTROL_CHANGE message.
** Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
** Windows 95/98/Me:** Included in Windows 95 and later.
** Header:** Declared in Mmsystem.h; include Windows.h.