Crossbench senator Derryn Hinch is ramping up pressure on Pauline Hanson's One Nation over the explosive recording of senior figure James Ashby proposing a secret arrangement for the party to make money out of taxpayers and candidates.

There could be more that is yet to emerge, Senator Hinch has said, predicting Senator Pauline Hanson and Mr Ashby, her chief-of-staff, face the possibility of criminal charges over the matter.

Following the publication of leaked audio this week, in which Mr Ashby outlines to a party meeting the "opportunity for us to make some money [out of inflated expense claims] if we play this smart", Senator Hanson said the idea was "knocked on the the head there and then" in another part of the discussion.

A further recording of the meeting, obtained by Fairfax Media, does not contain Senator Hanson's rejection of the idea and Senator Hinch has predicted "there is some more stuff to come out that I'm totally not aware of".