Old iPod Touch Selectively Not Connecting to Store

I'm still using an old iPod Touch for my podcasting, I'm not totally sure which version it is but the software updates have topped out at iOS 5.1.1. The problem I've just started running into recently is that when I try to access a handful of podcasts through the Podcast App Store I get a "Cannot connect to iTunes Store" prompt. It only happens for a few different podcasts and it's only become a problem that I'd like to get solved now that I can't access a new podcast that I'd like to subscribe to. Is there a fix to this or are some podcasts just starting to use technology that my old iPod can't read?