HDMI 2.1 Sound issue

How long is your cable? the longer ones are worse ,so you should always use short ones for your monitor for the best performence.
Is your mainboard/gpu maybe sitting loose?
Are you using Win11/10?
Are you using blue tooth headseat ?
Do you have internet connection probblems?
Is your screen freezing or is only the sound glitched?
Do you use RGB especially software for rgb?
Did you always had the issue or did it appear randomly after a longer period of time with the same setup?
Is the same thing happening if youre streaming towards your tv?

Since it's a known issue.. I would just connect another audio cable. Crackling would make me nervous.
I'm sure your TV has optical, so if your comp does too, then 👍

That's my lazy non-solution ;-O

Thanks for the quick answers. I'm well aware it's a first world problem and no biggie at that. Video signal isn't affected only sound which is beginning to distort and crackle randomly after a couple of hours of gaming/watching content ONLY. It's easily fixed by disconnecting and reconnecting the cable but it annoys me nevertheless. Cable length is 5 meters and as video signal gets through flawlessly sound should too.
As I built the rig a few weeks ago I'm sure motherboard and GPU are seated as they should.

In my opinion the video card is to blame as my tv is connected with my gaming laptop also which hasn't this issue as the laptop is limited to HDMI 2.0 = 4K@ 60Hz output.
As far as I found out the problem occurs in 4K 120Hz or 8K 60Hz output format only.

I'm using Win10x64 Pro as OS. I'd love to hear from other user's experiences with a 30/40 series Nvidia GPU or an 6xxx/7xxx AMD one connected to a tv over HDMI 2.1 especially in view of a future buying decision.

You had me at 65 inch for a main monitor.

https://i.imgflip.com/260nag.jpg

I don't have a 30 series, but I'm guessing this is software, rather than hardware, unless your hardware ports or the cable is damaged. Assuming those are in good condition, I'd check drivers, or other things. From what I read apparently lowering the res might help. It's possible over many hours that the ports get hot too, causing said interference, but just plugging out and fixing it by instantly plugging it right back in indicates that's likely not the issue.

Sound problems are the worst, I've replaced many speakers over the years just because of minor crackles so I can understand why you would like this fixed. I'm no expert but as previously mentioned shorter cables are a win with any electronics, also quality is important. Having said that to me this doesn't seem like a cable issue as you aren't getting it for a long period, I guess a cheaper cable though could still cause this. To me it would lean more towards a heat or software issue.
Does the cable end or port feel hot when you remove it from the card to change ports?
Also have you tried a different port on the tv itself?
Have you tried different Nvidia drivers? (older even)
What are the video card temperatures like when this issue is starting to occur?
Are you able to try a different video card (i.e. do you have a spare to try)?
Have you updated the tvs software?
I'm presuming not but is there any video degradation when this crackling starts?
Clutching at straws really but in the end it'll likely be one issue and not a combination of multiple so the best way to fix it is to start swapping out parts like you did with the cable.

Based on your tried solutions so far, I would suggest trying another TV. If it works with no problem, it is the TV; if not, it is the GPU. If it works fine for 4 hrs, it could be a cooling issue too.

Have you tried lowering the refresh rate?
You said the issue does not occur with your laptop, but you should also test 4k@60 on your PC. If it still occurs, then the issue is with the PC, but if not, then it's still possible that your TV can't handle that refresh rate for a longer period of time.
If you test this, make sure you use the same color format, HDR etc settings as your laptop.

I found out for the first time that I was blacklisted. Feeling like a VGA cable ☹