I’ve found it. Go into the ja_comments admin panel and under the settings tab you will find a layouts and plugins option. Click on that and you will see 2 tabs at the top, one says layouts and the other says plugins. Click on the plugins tab and you will see a list of options. One is the Addthis plugin and the other is the Addtoany share button. Disable these.
No, I have no idea why both of these are there. Maybe the devs added all the different types so the user could pick one. It does seem they cause problems if you have more thabn one enabled.