If your RSS feed isn’t valid, it may be due to a few different reasons:
 

Please check your Content Settings page and make sure that you do not have anything in your Subscriber Redirect field.

 

By putting another URL into this section, you will break your RSS feed, and it will no longer work. This field is if you no longer want to use SoundCloud as a hosting provider, and want to redirect your podcast’s subscribers to a different hosting provider. 
Remove the URL from this section, and click save. From there, your RSS feed should function properly again. 
 

Please check your Content Settings page and make sure that you do not have anything in your Stats service URL prefix field.

Please note: This section is only for Podtrac or Blubrry users. You should not fill in this section with anything but 'http://www.podtrac.com/pts/redirect.mp3'. If you’re using Blubrry, copy/paste your custom redirect URL displayed in Powerpress under the “Services and Stats” section. Putting anything else (such as a FeedBurner link or website address) will break your RSS feed. 
 
Remove the URL from this section, and click save. From there, your RSS feed should function properly again. 
 

If your track is private, it will not appear in your RSS feed. The RSS feed only populates with public tracks. To make your track public and in your RSS feed, go to the track’s edit page and change the privacy settings. You can read more about this here.