speaker-recognition warning: frame length is greater than FFT size

[wenyeye4]

please help on the issue of warning:
warning: root: frame length (1200) is greater than FFT size (512), frame will be truncated. Increase NFFT to avoid.
/home/pi/try_lyt/try1.wav -->testaudio, score-->1.0, the number 1.0 is also strange, it should be something like 0.94 or the other ratio