It's probably in your code or one of the plugins that is loading third party content as Saturn shows no problems. Did you recently add any new plugins that rely on 3rd party content?

You could easily test that theory by installing a barebones version of Wordpress in a subdirectory of your account using the Softaculous script installer. It should only take about 5 minutes to test. If the barebones version works then you need to analyze the modules you have installed.