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WODM_SETPLAYBACKRATE
 
        This message is sent to a waveform output device driver to set
        the playback rate for a device.
 
Parameters
        DWORD dwParam1
            Specifies the new playback rate setting. The rate is
            specified as a fixed-point value. The high-order word
            of the DWORD contains the signed integer part of the number,
            and the low-order word contains the fractional part. The
            fraction is expressed as a WORD in which a value of 0x8000
            represents one-half, and 0x4000 represents one-quarter. For
            example, the value 0x00010000 specifies a multiplier of 1.0
            (no pitch change), and a value of 0x000F8000 specifies a
            multiplier of 15.5.
 
        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 the playback rate.
 
Comments
        Driver support for playback rate changes is optional. When a
        driver receives a WODM_GETDEVCAPS message, it should indicate
        support for playback rate changes by setting or clearing the
        WAVECAPS_PLAYBACKRATE bit in the dwSupport field of the
        WAVEOUTCAPS data structure. If a driver supports the
        WODM_SETPLAYBACKRATE message, then it must also support
        WODM_GETPLAYBACKRATE.
 
        Changes to the playback rate alter the pitch of a waveform
        during playback and are usually implemented by the driver by
        skipping or repeating samples. For example, if the playback
        rate was 2.0, the driver would play every second sample, at the
        original playback rate.
 
See also
        WODM_GETPLAYBACKRATE, WODM_SETPITCH
 
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