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AUXDM_SETVOLUME
 
        This message is sent to an auxiliary audio device driver to set
        the volume level for an auxiliary audio device.
 
Parameters
        DWORD dwParam1
            Specifies the new volume level. The high-order word contains
            the right channel setting and the low-order word contains the
            left channel setting. A value of 0 is silence, and a value
            of 0xFFFF is full volume. If the driver does not support
            both left and right channel volume changes, it uses the
            volume specified in the low-order word. The driver will
            probably not support the full 16 bits of volume control and
            should truncate the lower bits if necessary. However, the
            original value requested with AUXDM_SETVOLUME should be
            returned with AUXDM_GETVOLUME.
 
        DWORD dwParam2
            Unused.
 
Return value
        The return value is an error code, or zero (MMSYSERR_NOERROR) if
        the operation is successful. Possible error codes are:
 
        MMSYSERR_NOTENABLED
            The driver failed to load or initialize.
 
        MMSYSERR_NOTSUPPORTED
            The driver does not support changes to volume level.
 
Comments
        Support for volume level changes is optional. Drivers must
        indicate whether they support volume level changes when they
        receive the AUXDM_GETDEVCAPS message.
 
        If a driver supports changes to the volume level with the
        AUXDM_SETVOLUME message, it must support queries with the
        AUXDM_GETVOLUME message.
 
See also
        AUXDM_GETVOLUME
 
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