Are both the server you are connected to and your client exactly the same version? Or at least both 3.2 or higher, or both less than 3.2: that release broke backwards compatibility for the faction and new global chat types.
If you are certain both the server and your client have the latest version of this module installed, maybe there is a bug in the code - I was a bit surprised not to hear any problems reported with the new system after it was released, since it was complicated and hard to test thoroughly; but maybe people just didn't bother to report stuff, since the system was deemed to work slightly better than the previous one... ?
One thing you could try: if global chat is failing to display, try send a faction chat message, then see if the global chat works; the faction message sends a bit more information, and might reset it back in sync.