Weird characters inserted before doctype

There are some weird characters that are being inserted before doctype declaration. Strangely it happens only on the home page and not on any other pages/posts. Firefox ignores it and displays the page properly. IE however inserts a line above the page, breaking the design in the process.

To see the code, go to https://www.appropriateit.org/, and change character encoding to western iso-8859.

I have combed through all the template headers with no luck in locating these offending characters. Any other ideas?

TIA.