I use
pRSS Reader. I think it works better than RSS Hub just because of the "Download Enclosure" feature in it.
As long as the site or blog you are getting the RSS feed from has the tracks or podcast listed within the post as streams and not just as a link, pRSS will pick them up and present them as "enclosures" at the bottom of the viewing pane. You can then click Menu > Download and the prog will download it to the enclosure folder. In fact, in the settings you can change the cache directory to your storage card for the downloads just in case its a large file.