HDMI audio is out of sync by about 1 to 2 seconds in any desktop in multiple linux distros. Two things that fix it. The first is turning TV ON and OFF and the second is suspending and resuming the computer. Both are getting rather annoying to do after every reboot to sync audio.

Is the audio AHEAD of or BEHIND the video? I have an HDTV (old one) that has audio outs and compensates for it's sync issue. Otherwise audio will always be AHEAD of the video since it takes a while for the TV to show the image. More of an issue if you don't output audio from the TV. Persistence across multiple distros probably means a hardware issue/quirk. Some TVs just suck. Have all the distros been .deb based ones? Various flavors of ubuntu? Tried fedora / arch or other non .deb based distros?

The audio is behind the video by about 1.5 seconds, odd right? When I use the Intel integrated graphics HDMI output, video and audio sync fine but it is only 30 hz at 4K. With the NVIDIA 780 GTX HDMI, audio lags every boot. I would think it was a driver issue but it occurs with both the free open source driver and the proprietary NVIDIA driver. No I have pretty much only tried debian on it as well is Ubuntu very briefly. I’ve tried many distros over the years but have settled on Debian for both my desktop and server. I just like it.

The audio sync’s fine with the NVIDIA 780 GTX HDMI in windows 7, which I have since wiped off my desktop given it is reaching end of life, no more updates, in Jan 2020. I pretty much had Windows 7 for gaming but linuxing gaming is rapidly progressing.

It's not a Linux issue. This is actually an engineering issue with the HDMI standard itself.

HDMI's Lip Sync and audio-video synchronization for broadcast and home video

Don't send audio over HDMI if you can avoid it.

(It's "fixed", as in it has workarounds available, as of HDMI 1.3. Some TVs have settings to explicitly enable these workarounds).

If it is related to audio being processed faster as the article you linked says then why is audio coming a full 2 seconds late, not early? Also it does not explain why the NVIDIA HDMI works in windows and Intel HDMI works in windows and linux.

Also the audio only sync's correctly if the TV is turned ON and OFF after logging into a desktop. Turning the TV ON and OFF while in the display manager before logging in has no effect. The same holds true with suspend and resume.