I have never seen or had this issue before but I'm finding on several of my sites that my entire website is repeating within Google adsense spaces. Through experimentation, I think I've narrowed it down to happening only when I visit my URL with www. For example www.mysiteexample.com is having issues but mysiteexample.com does not.

I don't see how this is even possible. Where to start? Is this simply some DNS issue with my web host? I hate contacting them and fear they'll screw things up even more.

Attached picture shows 2 ad spaces side by side with website repeating within.