Google Adsense issue.

I am having some issues with Google adsense that I am having trouble ironing out. I have 4 Google ads set up for my homepage. 2 of them show, 2 do not. My WordPress is set up with the Canvas theme from Woo Themes. I have a Image half banner in the header that shows up, and an image wide skyscraper on the left sidebar that shows up. At the bottom right sidebar I have a text only Medium Rectangle that will not show up, and in the left sidebar above the skyscraper I have a 160×90 link unit ad set for 5 links that won’t show up. All ads show up in all other pages and posts but not the home page. Any clues as to why this is happening will be greatly appreciated.