Here is a download link for the whole Front Row 30 minute programme
from the BBC web site

http://downloads.bbc.co.uk/podcasts/radio4/frontrow/frontrow_20140917-2010a.mp3

Sorry - I can't seem to make a blue clicky,
and I don't know if this link will work outside the UK

The interview with Joan Baez begins just before the 6 minute mark, and lasts about 10 minutes.