fix wordpress header solostream wp chatter theme

If you look at my site [login to view URL] you will see the header is messed up and missing. When you hover over the navigation tabs, they show up, but the logo does not show up. I can change ftp permissions and then it shows up but the logo doesn't show. It shows both the site title/description and the wp chatter theme logo (original logo) instead, and they are on top of each other. I need someone to fix this for me.