I can't get the RSS Feed macro to work with Confluence Feed Builder url

[Sisi Yao]

I'm trying to use the RSS Feed macro to display a feed I built with the Confluence Feed Builder. I have no problem building the feed or adding the Feed macro to the page. However, the url does not seem to work. The macro keeps generating the following error on the page:

Screen Shot 2015-10-29 at 11.40.27 AM.png

I tested out the url in another RSS Reader and it's working just fine.

I have whitelisted the domain in Confluence so that's not the issue.

[Jonathan Simonoff]

I'm having a similar problem, although I get a different error: 

Error rendering macro 'rss' : java.net.SocketException: Connection reset

I'm using Confluence 5.5.  Atlasssian do you have any help to offer?