Warning when training

I am getting the following:

WARNING:root:frame length (1200) is greater than FFT size (512), frame will be truncated. Increase NFFT to avoid

Does it have a significant impact? And how do I fix it?
There is a variable in deepspeech.cc ‘N_FFT = 512’, would this be the right way to change it and if yes, should I set it to 2048 as it appears we have to set it as a multiple of 2?