Quote from ShroomismFubar + Naxx = FUBAR.
Everytime I zone into Naxx my Fubar goes all haywire. It's set to auto-hide. But both bars show up, and freeze.. I can't access the menu.. or change anything in Fubar.. it's just frozen there. Relogging doesn't fix the issue, neither does zoning out of naxx.. have to disable the addon, then re-enable it while outside of Naxx.
I am having this same problem, any other info on this? could it be a conflict with another addon?