My headers have been working fine, displaying for all users. I recently updated my site header, however now when not logged in the image does not appear. (the box, title and overlay colours appear as normal just time background image). If I log in as Admin, I can see the image in the header fine (this goes for when using the private feature in the browsers too) but when I log out. The image goes away again.
This only affects the updated image. Other header images that where already there are still visible regardless of being logged in or not.
On further testing, nothing is updated when the user is logged in. I have added the word test to the content box. It appears when logged in but no when not logged in.