Can’t download KCRW podcasts

I’m subscribed to many podcasts in iTunes and they’ve all been downloading without problems for months. In just the past few days though, I can’t download just those podcasts that are KCRW series: “KCRW’s Left Right and Center”, “KCRW’s The Treatment”, and “KCRW’s Unfictional”. Each one fails with error 12004, and if I click on the exclamation point next to the title, it reads: “There was a problem downloading ___. The network connection was lost. Please check that the URL is correct and the connection to the network is active and try again.” My network connection is fine -- all the other podcasts download without this error. What might be different about these particular podcasts?