factor() in docs

[fmailhot]

API docs for audio augmenter all say the same thing for factor, i.e.

Input data volume will be increased (decreased). Augmented value will be picked within the range of this tuple value. Volume will be reduced if value is between 0 and 1.

see e.g. https://nlpaug.readthedocs.io/en/latest/augmenter/audio/speed.html

[makcedward]

Thank you for reporting it. Will fix it in the coming release