Been having issues since early access. Cutscenes were unbearable to listen to.
At some point during the first week the audio bugged and locked up my entire game, then subsequently crashed my computer. I'm not sure if these issues sped up the process, but my hard drive began to fail hard after this. It was rather old, however I had no issues and no hint of issues prior to the audio and fps lag of Endwalker.

Since replacing the HDD and also getting an SSD, I completely reinstalled the game and this time did not install the new paid spatial audio feature. The stuttering still continues, as well as the fps drops. It's not *as bad* as it was on my old hard drive, but it's still a bit disorienting. I've tried everything except switching to DX9, and the reason I haven't is because I've seen too many people say that switching did not help or they were unable to even open the game after a while even if they swapped back to DX11. I don't want to risk that happening to me, since at the moment I can still play the game, it's just highly inconvenient.

I hoped the patch would fix things and while I had no stutters the first three floors of Pandaemonium, the 4th floor was a disaster. Everything from the BGM to the combat sounds were stuttered entirely. At that point I tried the suggestion of lowering the hz/bitrate, and that removed all sound from my game. It stopped the fps drops that accompanied the audio lag for the fourth floor at least.

Since relogging I've had audio stutters happening again, whether it be in dungeons or even me progressing the MSQ on my alt and fighting small mobs at destination points.
I'm currently running an AMD FX-4300 and while I know that's old and will soon be replaced, I have no problems with any other games and I never had problems with FFXIV until 6.0. I wondered if it was an AMD problem but I've been seeing people with Intel describing these issues as well.