Of course i can only be talking about one of two things terrible server lag or the dreaded alt+tab/lost focus issue (Unable to detect DirectX device).
in this case it's the latter, here is a few threads i've found feel free to post any i've missed.
http://forum.square-enix.com/ffxiv/t...ght=fullscreen
http://forum.square-enix.com/ffxiv/t...ght=fullscreen
http://forum.square-enix.com/ffxiv/t...ght=fullscreen
http://forum.square-enix.com/ffxiv/t...ght=fullscreen
http://forum.square-enix.com/ffxiv/t...ght=fullscreen
and finialy a old dev post with very little information;
http://forum.square-enix.com/ffxiv/t...l=1#post108951
there are so many "fixes" suggested that do not work, if you know how SLI/Xfire, directx, vsync work (ref: needing to play in window mode) you'll know the only real fix is for SE to get it sorted.
Anyway what i'm looking for is links to posts about this issues (or a "Like" if you're suffering this isse too) and not suggestion on "fixes" in the hopes that the dev team will take this issue seriously, and at least gave us some real information, and not "we'll look into it" that just sounds to me like a "/meh, we'll look in to it maybe".