Realtek USB audio has S/PDIF sound delay

When I run audio from the motherboard S/PDIF connector into my DAC, there is a delay of several seconds before sound starts. When I start playing a sound source, I miss the first part. The problem isn't with the DAC since everything works perfectly using the S/PDIF output with Realtek UAD systems. Yet 2 different motherboards using Realtek USB audio (ASUS & MSI) have the delay. Sound from the regular analog output works as it should, but I'd rather use S/PDIF out since my external DAC is much better than that in either motherboard. Anybody experienced this and found a cure? I'm suspecting it could have something to do with USB being asleep and then waking when it gets a signal. Incidentally, the problem still exists when I use the Microsoft USB audio driver, so it's apparently not a driver fault.

Hey bud

The old sound lag issue, damn i had that on several motherboards over the years.

First things first.

So, youre using the motherboards onboard sound? If youre using the motherboard spdif output i assume thats the case.

A few things to check over in the Bios.

Make sure your audio front panel output is set to HD and not AC97.
Are you using DVi or HDMi for the audio?
Some motherboards, you can disable the DVi audio out.
Make sure that any other PCIe or PCI input connection isnt using the same IRQ as the onboard sound.

Pain in the arse is the damn Audio lag.

Youre not using dvi or hdmi are you?

Its spdif !

Sorry to ask a silly question

The "USB" is just the link between the realtek audio chip and the CPU.

CPU---USB link---Realtek chip

If it has a wake up problem, then it would also give you 3.5mm delay.

Thanks, Plugins.

Motherboard S/PDIF out via optical cable into DAC. RCA cables from DAC to 5+1 receiver.

Right ok, so youve got two inputs and outputs.

Maybe the sound is ok to the DAC, and then the lag is appearing from the DAC to the Amp? Maybe?
There is a problem in between i think.

With the RCA not being digital as we say, maybe the lag is appearing in between the digital signal and the analogue source.

Do you have any headphone output on the DAC?

Thanks, sandyt.

Maybe I'm misunderstanding something here, but that sounds as if the USB audio connection is confined to the motherboard. If that's the case, maybe I need to be looking at USB settings in the BIOS rather than in Windows. I already went into Windows power options and disabled USB selective suspend. That didn't help.

- - - Updated - - -

Pluginz, I don't think there's anything wrong with the setup. I did try bypassing the DAC and plugging the optical cable directly into the receiver since it has a built-in DAC. Still a delay. That left the optical cable as a possible problem, so I switched it out with another. No joy. Running a Y cable with a 3.5mm stereo plug to 2 RCA plugs from the motherboard analog out and into the receiver has no audio delay, so it's just the S/PDIF out on both this ASUS motherboard and an MSI motherboard, both with Realtek USB audio. S/PDIF out on my previous motherboard with Realtek non-USB audio and exactly this same setup (even the same Windows 10 Pro installation) worked perfectly.

Okies, lets see if we can get any closer.

Go to the start run menu, type 'msconfig'

'Highlight' system information, and then click 'Launch'

In the Information click, 'Hardware Resources', then 'Conflicts / Sharing'

Scroll down the list until you can find your sound card, which will be displaying the output.

Being the audio, it will probably be IRQ 16 or IRQ 18.

Let us know what you find bud

Pluginz, I find High Definition Audio Controller on IRQ 16 & IRQ 17. No IRQ 18 listed. Status on both is OK.