As a huge fan of Podcasts, I tend to veer towards ones that will be of some use to me in terms of quizzing and one I have recently completed is the excellent "History of the Heavyweight Championship" by Steven Bunce. I haven't put any links up as its available on most podcast sites (Podbeam or Castbox being my preferred two).
Each episode lasts around 20-25 minutes and focuses on a single year from the era. At present the series covers 1960-1979, one of the most exciting eras for boxing! As at the time there was only one real undisputed champion for much of the era, there often aren't a great deal of fights to cover so Steve goes into great detail about the fights and fighters from the era! Well worth a listen! I have picked up so much from it quizzing wise.