I just wanted to note what i've observed about the issue, and there was a post over a week ago that seems to comfirm it. The only npcs that seem to lock up on people are ones near the Synergy Furnaces. Northern Sandy OP and Porter moogle are within view of these npcs, they and the ones near the woodworking guild are the only areas there i've experienced locking or freezing up on npcs. Southern Sandy I've had lock ups near the ones next to the guilds on the west side of town as well as the Aht tele npc next to the furnaces near the MH. I've had the new abyssea npcs in port lock up on me one when i came from the zone from N sandy once which was in view of the furnaces once again. So from this I would have to say if nothing else those Furnaces seem to be a cause to the lock ups, i'm sure theres more npcs near these furnaces causing these freezes elsewhere, I just don't talk to every npc in town lol. Side note used to be the work around in N sandy was talking to the 2 npcs accross from the OP NPC however as the updates went on they tend to freeze themselves.