Re: females generally have higher pitched voices
"So saying female voice is quieter or masked voice by fan or traffic not a good excuse for the lack of training on the AI with female voices."
It's not a good excuse for lack of training with female voices, as opposed to male voices, which is one problem with the training on data sets. However, if external noise due to traffic and domestic/office noise is in the same frequency range as the female voice, or if the female voice is generally quieter, then the S/N ratio will be lower at the recorded source.
In this situation, you can't improve things by turning the volume up. If you ran some fancy noise reduction process over it then the male voice recordings would be improved as well and so the male recordings would still have a better S/N ratio than the female recordings.