Note: There is no "one size fits all" redirect. Below are general guidelines.
Log into your Libsyn account and Go to Settings -> Edit Show Settings in the top menu:
2. Then, click on Redirects in the left menu:
3) Put in your redirect for both the RSS feed AND website:
Use this article for information on how to find your RSS feed in Megaphone. Double check that the Megaphone feed is correct and working properly (you can test by opening the feed in a new tab).