The short segment Permeate (part of Off Track) produced by Miyuki Jokiranta features an interview with Perdita Phillips about walking and sound in her practice. It includes narrative extracts from the sound walk To Meander and Back.
You can listen to it here http://www.abc.net.au/radionational/programs/offtrack/permeate3a-perdita-phillips/3932726 (download might possibly be restricted to Australian isp addresses).
The sound art walking work continues with The Sxith Shore and with the up-coming cusp.