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Realtek ALC4080 Audio Problems. Sound Cuts out with Loud Hiss.

dylan_k

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Hello, I'm new to this forum but you all seem very knowledgeable and I'm stumped here. Maybe someone here can think of a new fix to try.

My trouble is with the sound (Realtek ALC4080) on a new motherboard (MSI z590 Torpedo) motherboard on a (mostly) new PC build.

Using the TOSLINK audio output, the sound will work normally for some time but suddenly and randomly the sound will cut out and a very loud hissing sound is output instead. It happens randomly and sporadically. Some days it won't happen at all, other days it happens several times every hour.

Any thoughts on what I can I do to make this audio output behave normally? Do you think it's a hardware problem or a driver issue?

Some notes from testing and research:
- Issue does not occur with any other audio outputs. TOSlink only.
- Tested, confirmed that the cable is not the cause.
- Tested, confirmed that the receiver is not the cause.
- Found several threads about this issue with the alc4080 on motherboards from a variety of manufacturers but I haven't found word of a fix.
- (It seems incredibly common for forum-posters to suggest "just buy a sound" card but that's a distraction from the issue at hand.)

Here's what I've tried so far:
- Windows, Windows Update, BIOS, and Drivers are all latest versions. Drivers via manufacturer.
- Tried resetting the CMOS but it didn't help
- MSI support suggested to disable Intel C State in the BIOS, but it didn't help. (Their other emails are poorly written to the point of futility.)
- Realtek support did not respond to my question.
 
This sounds to me to be a hardware problem.
 
Sound cards... thing of past. With the amount of EMI other components generate, they're not a wise solution. If you want to upgrade your audio, look at DACs or just use 3.5mm.
 
Sound cards... thing of past. With the amount of EMI other components generate, they're not a wise solution. If you want to upgrade your audio, look at DACs or just use 3.5mm.
I'm first interested to know whether I have a faulty motherboard.
 
Doesn't necessarily mean the board is faulty, onboard sound is affected by EMI as well for example. Why not just use 3.5mm? It's not like you're going to lose on a lot of sound quality.
 
SPDIF can also get out of its place easily, I'd check connection ends again.
 
You should be more specific. All soundcards have DACs. His receiver, also has a DAC. Maybe you do not understand what a DAC is?
 
You should be more specific. All soundcards have DACs. His receiver, also has a DAC. Maybe you do not understand what a DAC is?

No, the point was obvious. It's your reading comprehension that failed to understand it. It was talking about a dedicated DAC that would sit outside of his case, to be used for audio processing.
 
No, the point was obvious. It's your reading comprehension that failed to understand it. It was talking about a dedicated DAC that would sit outside of his case, to be used for audio processing.
OP is already using a dedicated DAC. It is the receiver connected via toslink.
 
OP is already using a dedicated DAC. It is the receiver connected via toslink.

A receiver works to amplify passive speakers, you need a sound device to make it work on the computer, which in this case could be a DAC, a sound card, onboard audio...
 
A receiver works to amplify passive speakers, you need a sound device to make it work on the computer, which in this case could be a DAC, a sound card, onboard audio...
TOSLINK (and coax, HDMI) receiver take digital signals, convert to analog via internal receiver DAC, then amplify that signal.
 
TOSLINK (or coax, HDMI) receiver take digital signals, convert to analog via internal receiver DAC, then amplify that signal.

Am I speaking with cows here? Do you fail to understand that you can not directly connect a receiver to a PC if the PC has no audio devices active? The PC needs some form of audio interface to process those signals. The only other way the receiver can work is by putting a USB stick or something to it, which would then be doing purely direct processing on itself.
 
Am I speaking with cows here? Do you fail to understand that you can not directly connect a receiver to a PC if the PC has no audio devices active? The PC needs some form of audio interface to process those signals. The only other way the receiver can work is by putting a USB stick or something to it, which would then be doing purely direct processing on itself.
The motherboard has the optical out; OP already described that.

@dylan_k Do check when playing content that the motherboard optical out red light is staying on. If there is cutoff, this is a hardware problem.
 
The motherboard has the optical out; OP already described that.

@dylan_k Do check when playing content that the motherboard optical out red light is staying on. If there is cutoff, this is a hardware problem.

AND that damn optical out is connected to the Realtek which works as an onboard audio encoder. You just failed to understand that I was talking about buying a separate DAC and came up with this. Maybe I should go bang my head against the wall instead.
 
AND that damn optical out is connected to the Realtek which works as an onboard audio encoder. You just failed to understand that I was talking about buying a separate DAC and came up with this. Maybe I should go bang my head against the wall instead.
Please do.

OP has requested us to see first if we can find the problem on the motherboard, before requesting to buy USB/PCIe to optical transceiver.
- (It seems incredibly common for forum-posters to suggest "just buy a sound" card but that's a distraction from the issue at hand.)
 
Please do.

OP has requested us to see first if we can find the problem on the motherboard, before requesting to buy USB/PCIe to optical transceiver.

And I've given him couple suggestions regarding that, mr. zero reading comprehension.
 
I tried some things again today:

- swapped out the cable for a different one
- disconnected all USB devices just to see if that might make a difference.
- reseated all the cards and cables on the board
- checked cables for anything touching that could contribute to magnetic interference, as I've read that's a good practice in general
- disabled "auto detect" for the front audio

The hiss returned despite these measures.

Curiously, it seems most likely to happen within 10 minutes of powering on the computer. If, after the hissing starts, I switch outputs to, say, headphones for a moment, and the switch back to the optical output, it sometimes works again.
 
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Do check when playing content that the motherboard optical out red light is staying on. If there is cutoff, this is a hardware problem.
Ok I've checked this. The red light stays on while the audio is playing normally. After the hiss starts up, I checked the cable again and the red light was still there. Unplugging the cable and plugging it back in, while in "hiss mode" did not make anything change either.
 
Did you check the receiver optical input? Did you try another optical source?
I'm not finding much more ideas though. It seems to me that it is either the output device sending incorrect data, or receiver not receiving/decoding the signal properly.
 
Same problem here with my KEF LSX hooked up via TOSLINK to z590 Carbon. As I have my speakers on 100% and control the volume with my PC, when it kicks off it literally destroys your ear drums and scares children and animals in a 5 mile radius. Sad times....
 
There is fix on MSI motherboard support site

Edit: Until now it works:)
 
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AND that damn optical out is connected to the Realtek which works as an onboard audio encoder. You just failed to understand that I was talking about buying a separate DAC and came up with this. Maybe I should go bang my head against the wall instead.

You should refrain from posting in the audio section. Audio processing DSP section and a dedicated sound device is not a only DAC, that term itself is vulgar and incomplete. The bus decoder part could be anything a matter of taste there.

Then you mish mash things and argue.

You critique towards Realtek digital sound is out of place and suggesting OP to buy another product instead of understanding the problem. Digital sound source either SPDIF or HDMI coming from PC is device agnostic, it can be bitperfect and doesn't care if it Realtek or anything else. If you do not need more than two channels then SPDIF is still a great solution, as you can galvanically isolate devices from PC and actually improve THD by removing possible ground loops and greater cable range like versus USB solutions.

I've experienced SPDIF instabilities in the past, for most those were driver problems, incorrectly handling interrupts. The IC is rather new, you should wait for new drivers, the bad news Realtek never posts change logs, so it is like you will never know, they will not answer either. Alternatively play around with power states. Disable C states that could cause the interrupts to desync the device etc...
 
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