Howdy Andrew,
Usually, that error indicates that your are requesting an image etc. from a non-secure location. To be a bit more clear, from an http:// vs. https:// . In this case I see that https:// www dot websites dot com dot au is throwing an error. So, they probably don't have an SSL Certificate installed or it's installed incorrectly.
If you have further questions on this, put a url up for your site. I can look deeper.
Paul






