DWORD GetStandardChannelMaskFromXmaMask(  
         BYTE bXmaMask  
)  

__inline DWORD GetStandardChannelMaskFromXmaMask(BYTE bXmaMask)
{
    DWORD dwStandardMask = 0;

    if (bXmaMask & XMA_SPEAKER_LEFT)           dwStandardMask |= SPEAKER_FRONT_LEFT;
    if (bXmaMask & XMA_SPEAKER_RIGHT)          dwStandardMask |= SPEAKER_FRONT_RIGHT;
    if (bXmaMask & XMA_SPEAKER_CENTER)         dwStandardMask |= SPEAKER_FRONT_CENTER;
    if (bXmaMask & XMA_SPEAKER_LFE)            dwStandardMask |= SPEAKER_LOW_FREQUENCY;
    if (bXmaMask & XMA_SPEAKER_LEFT_SURROUND)  dwStandardMask |= SPEAKER_SIDE_LEFT;
    if (bXmaMask & XMA_SPEAKER_RIGHT_SURROUND) dwStandardMask |= SPEAKER_SIDE_RIGHT;
    if (bXmaMask & XMA_SPEAKER_LEFT_BACK)      dwStandardMask |= SPEAKER_BACK_LEFT;
    if (bXmaMask & XMA_SPEAKER_RIGHT_BACK)     dwStandardMask |= SPEAKER_BACK_RIGHT;

    return dwStandardMask;
}