itunes doesn't download podcasts

Hi all. I'm on a HP laptop running Windows 10. A few days ago iTunes started jamming up really hard, working very, very slowly; I tried restarting iTunes, but that didn't work, so I restarted the computer, and it works! But now it's not downloading my podcasts. They show up in the list, and I can manually download them, but it should do that automatically. Any ideas what's going on? I haven't changed anything, and everything's up-to-date; I'm baffled.