I cant believe no one replied,
ANYWAY, I had the same exact problem today, I was checking all the dam xml files and no luck, I found the podcast xml and put a space between the tags that look simialr to try and insure they would not be strung together then DEACTIVED THE PODPRESS PLUGIN AND LOADED THE SITE AND CHECKED THE PODCAST LINK IN THE SIDE BAR THEN RE-ACTIVATED THE PLUGIN AND IT SEEMED TO WORK.
hope that helps, good luck fellow podcaster!