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WODM_SETVOLUME
 
        This message is sent to a waveform output device driver to set
        the volume for a 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 WODM_SETVOLUME should be
            returned with WODM_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
        Driver support for volume level changes is optional. When a
        driver receives a WODM_GETDEVCAPS message, it should indicate
        support for volume level changes by setting or clearing the
        WAVECAPS_VOLUME and WAVECAPS_LRVOLUME bits in the dwSupport field
        of the WAVEOUTCAPS data structure. If a driver supports the
        WODM_SETVOLUME message, then it must also support
        WODM_GETVOLUME.
 
See also
        WODM_GETVOLUME
 
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