Link header image doesn't work

There’s an option in Graphene Options –> Display called “Link header image to front page” that doesn’t seem to work; I can’t get the header image to link to the front page no matter what combination of settings I use. I’ve turned the header text display on and off and have set the Reading settings to “latest posts” and then tried “static page” instead, but no dice. Can’t get it to work with the default images or a custom image.