Having the same issues. The stutter is constant. At high peek times in the server I just lose audio entirely and it won't come back until I restart the client. And since that's happened during peek hours it's nearly impossible to get back in to the game for 2+ hours. Direct x9 or x11 doesn't matter, it's done it on both. I've tried uninstalling and reinstalling ffxiv and multiple reboots of my computer and nothing has worked. At this point it's extremely disheartening and frustrating because audio is so integral to the cutscenes and story.