Random sqeuence of CPTs on initial listing

I need to have the initial listing of CPTs (which in my case are practitioners in a profession) to be random. Either I have missed something obvious, or it doesn’t seem to be possible. Once a “list all” or a search has been made, I can have the listing displayed in a random order, but the initial order they are displayed in seems to always be alphabetical.

Here is the page I have the problem with – the practitioners don’t want the list sorted, because the people at the top of the list will always be seen first and have a competitive advantage: http://hk-uk.co.uk/locations/

How can I force the initial listing to be in a random sequence? Thanks.