can't download episodes from your feed

Your media file URL is given as

https://www.dropbox.com/s/mecb2drzp7d72po/DRZTest.mp3?dl=0

This leads to a web page containing a download link for the file, which won't work. You must provide a direct link to the actual file, and the test is that when you enter the URL in Safari or another browser it plays in the browser, not in a web page, and embedded player, or forces a download. It's also advisable not to use https (secure connection); and the URL must end with .mp3 or iTunes won't know it is a media file. I don't think Dropbox is going to be a satisfactory place to host your media files. Any normal webspace server will do provided that it accepts 'byte range requests' (the method used by iPhone to access the files). If you try another server and post the URL I can test for that before you submit.