Help with broken RSS Feed Please!

I switched to a new theme on my blog and my RSS Feed is no longer updating. I tried validating it and get this error:
Server returned HTTP Error 301: The HTTP server returned a redirect error that would lead to an infinite loop. The last 30x error message was: Moved Permanently [help]

line 1, column 0: XML parsing error: <unknown>:1:0: no element found [help]

In addition, interoperability with the widest range of feed readers could be improved by implementing the following recommendation.

Feeds should not be served with the “text/html” media type [help]

Can someone please give me some ideas of how to fix this? I have tried everything I can think of.

Thanks!