Sorry for the troubles you're running into. That's not something we've heard of before, but we'll gladly help how we can.
First off, I'm assuming you are using jReviews, correct? If so, what version?
Beyond that, can you leave the JFBCSystem plugin enabled and then:
* Try disabling any Open Graph plugins you've installed an published to see if that stops the issue from happening.
* Disable the JFBConent plugin and see if that stops the problem
* Let me know what version of MySQL you are using, or, if another database engine, what that is.
Let me know if any of the above helps narrow things down. Hopefully that makes progress, but if not, we can have other suggestions to get you moving.
Thanks,
Alex