Why i get mRateScalar=0 in log ?

Question

  OSStatus recordingCallback(void *inRefCon, 
     AudioUnitRenderActionFlags *ioActionFlags, 
     const AudioTimeStamp *inTimeStamp, 
     UInt32 inBusNumber, 
     UInt32 inNumberFrames, 
     AudioBufferList *ioData)
   { 


  SInt16 noi= SInt16(inTimeStamp->mSampleTime);
 printf("\n%d", noi);
 noi= SInt16(inTimeStamp->mRateScalar);
    printf("\n%d", noi);
       noi= SInt16(inTimeStamp->mHostTime);
   printf("\n%d", noi);
   noi= SInt16(inTimeStamp->mFlags);
  printf("\n%d", noi);

-5312

0

-32170

3

printf("\n%f", inTimeStamp->mRateScalar);

0.000000 - I wait 1.00009 or 0.999996