Hm… It’s kind a strange. Maybe it is related to your permalink stucture. I know that WP render RSS feed for any page. Did you try to display RSS feed manualy? Will that solve your problem?
Site feed should be on /feed/
Also, it can be found on /category/your-category/feed/
as well as on /tag/your-tag/feed/
Just put /feed/ in place where you need and that should solve your problem.