Good afternoon and thank you for posting on the Final Fantasy XIV Technical Support Forums. I apologize for the delay in our response.

What kind of headphones are you using? Do they have their own program or set of drivers?

You mentioned that they are bluetooth headphones, do they have a wired option? Does this make any difference?

You may want to try a clean boot as well. Simply open the task manager and select the 'Start up' tab. Disable everything here and restart the PC. This will make sure that no background processes are interfering with the game.

Also, check the Sounds Settings under the System Settings. Make sure the 'Voice' option is at full volume.

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