Good morning and thank you for posting on the Final Fantasy XIV Technical Support Forums.

The game will handle audio with the default audio device only. When you remove the audio jack, you are removing the default audio device from the game, resulting in a crash. To avoid this, do not unplug the the speaker/headphones/etc. from the audio jack while the game is playing. If you wish to change the audio device, simply close the game, switch out the device, and then restart the game.

We hope we can be of assistance in helping you enjoy the exciting world of Final Fantasy XIV!