Adware plague in the apartment

Several computers in my apartment have all come down with this odd adware outbreak! A window on the right side of the screen pops up called "around the web" and has three ads listed. If I browse through private mode (firefox) it doesn't always come up but sometimes it still does. Or if I go to some websites (youtube, google or fuyjunk) it doesn't show up at all. So far it hit my laptop, desktop and boyfriend's laptop. It shows up when I go to places like Deviantart or Furaffinity but no one else is saying the site is giving them trouble. I have adblocker on firefox, I've tried scaing with malewarebyte, reinstalling firefox, and flash player and clearing the history/cookies. If anyone could help me out I really appreciate it! All three computers are using windows 10 and we use the same wireless router.