1 Topic by cjunekim (edited by cjunekim 2021-01-17 11:17:21)

  • Registered: 2021-01-17
  • Posts: 30

Topic: Periodic pops from Digiface USB's ADAT output?

Hello

I just received my new Digiface USB and was really excited to test this. However, it was really disappointing.

My setting is:

Windows 10 Pro 64bit
Digiface USB
Focusrite Scarlett 18i8 2nd gen

I have been using 18i8 for years without an issue. The buffer size is 64 and never had an issue.

Digiface's 2nd ADAT output is connected to the ADAT input of 18i8 via an optical cable. That's the only connection between the two. Digiface's Clock Source is set Internal. 18i8's Clock Source is set ADAT. The sample rates of both are set to 48khz.

The speakers are connected to 18i8's monitor outputs. In the Focusrite Control, ADAT 1-2, 3-4, 5-6 are added and they are directly connected to the Monitor Outputs 1-2.

Now I'm not playing anything from the OS. Waiting in silence for a while and I can start to hear pop noise from ADAT 2, 3-4, and 5-6, except ADAT 1 only. The meter indicated -0.6 dbfs noise came in. It seems somewhat periodic. Once in a couple of minutes.

The TotalMix shows there was no such signal sent through the hardware output. But Focusrite Control shows the pop signal received by the meter.

I tried various buffer sizes' of Digiface : 64, 128 and 256. All the same.

Sometimes, after booting, there is almost a periodic pop noise coming every second or so.

Have a look at the screen recording:

https://i.imgur.com/EG5mMKs.gif

When this happens, all the audio play makes continous crackling noise.

What am i missing here? This is my day one of my first RME product, and I had a great expectation.

BTW, I found a line from the manual that says "All devices connected to the Digiface USB must be properly configured for Full Duplex operation." What does it mean? Can it be somehow related to this?

  • Registered: 2019-10-01
  • Posts: 675

Re: Periodic pops from Digiface USB's ADAT output?

Hello!

I don't think there is a problem with your Digiface, but let's check a few things first!

Can you check if the ADAT Out 2 Port is set to "SPDIF"?  You can do that at the Driver settings Tab. If it is, set it to "ADAT"!
Can you try with a different Optical cable?
Did you check if the cable is fully inserted in both devices? There is a small click you can feel, when the cable connects firmly!
Do you have any other devices connected?
Also, in TMFX, which Outputs have you configured for your Main Outs?
Does this happen under ASIO Operation? When you open your DAW and have the RME ASIO Driver selected?

About the buffer setting, it's not the buffer setting by itself that matters, but the actual Round Trip Latency!

RME Gear: Digiface USB, HDSP 9632
  • Registered: 2021-01-17
  • Posts: 30

Re: Periodic pops from Digiface USB's ADAT output?

Thanks for the reply. See my answers below.

MetalHeadKeys wrote:

Hello!

I don't think there is a problem with your Digiface, but let's check a few things first!

Can you check if the ADAT Out 2 Port is set to "SPDIF"?  You can do that at the Driver settings Tab. If it is, set it to "ADAT"!

Yup. It's ADAT already.

Can you try with a different Optical cable?

Yup. Tried with 3 different cables.

Did you check if the cable is fully inserted in both devices? There is a small click you can feel, when the cable connects firmly!

Yup. Checked.

Do you have any other devices connected?

Yeah. I ran UsbTreeView to see the usb topology. I even tried my Digiface and 18i8 taking the whole usb host controller each. BTW, I have 3 usb host controllers on my computer. Two Intel on the MB, and one Renesas by PCIE card.

Also, in TMFX, which Outputs have you configured for your Main Outs?

Digiface's ADAT output 2 is going into 18i8's ADAT input. So digiface Hardware output 9/10 is going to 18i8's ADAT.

Does this happen under ASIO Operation? When you open your DAW and have the RME ASIO Driver selected?

Yup. When nothing is running on my computer, it pops. When DAW is open, it pops as well. I tried to record the popping noise but I couldn't. It's silent on my DAW.

About the buffer setting, it's not the buffer setting by itself that matters, but the actual Round Trip Latency!

Yeah. My usual buffer setting for other audio interfaces are 64, 128 or 192. I tried those values with Digiface and all had the same issue.

  • Registered: 2019-10-01
  • Posts: 675

Re: Periodic pops from Digiface USB's ADAT output?

Thanks for the info!!

Time to troubleshoot!! smile

1st Test:

This is rather obvious, but just for the sake of it, unplug the Focusrite from usb and optical connection.
Plug a pair of headphones in the DigiFace USB and check for any popping audio.
I don't think you will hear anything, because it would have been recorded in your DAW, when you checked the first time.

2nd Test:

Re-connect the Focusrite with the DF Usb via optical, and also, connect it to its USB Port.
Save the Focusrite Mixer Routing on it, disconnect it from Usb and check if you have audible pops(Focusrite stand-alone operation) from your monitors.

If you do hear pops, proceed to:
3rd Test:

I think the real suspect is the UsbTreeView App that you are using.
And this feature, in particular:

Safe removal, device restart and port restart

from this page: https://www.uwe-sieber.de/usbtreeview_e.html

I think that it's, continuously, monitoring the Usb Port and somehow messes with the Usb controller and its power settings.

So, I 'd suggest to disable the App or uninstall it, connect the DigiFace to a port that's coming directly from the MoBo's Cihipset,
and then go to:
Device manager -> Usb controllers -> Usb Hubs -> Right click on the one the DF Usb is connected to -> Properties -> Power Management -> UnCheck the "Allow windows to turn off this device" Option.

Waiting for update!

RME Gear: Digiface USB, HDSP 9632
  • Registered: 2021-01-17
  • Posts: 30

Re: Periodic pops from Digiface USB's ADAT output?

cjunekim wrote:

Hello

BTW, I found a line from the manual that says "All devices connected to the Digiface USB must be properly configured for Full Duplex operation." What does it mean? Can it be somehow related to this?

Can anyone answer this please?

6 Reply by ramses (edited by ramses 2021-01-18 07:37:43)

  • ramses
  • DAW Mastermind
  • Offline
  • From: UTC+1
  • Registered: 2012-10-14
  • Posts: 13,161

Re: Periodic pops from Digiface USB's ADAT output?

You need to read this statement in its context of clock synchronization.
Lets assume the Digiface USB is clock master and you want to connect a preamp.
Then its not sufficient to connect only the preamp to the Digiface USB with one TOSLINK cable.
You also need the other direction to transfer the clock signal.

I think this is meant by full-duplex operation, that there is a digital connection in both direction
and that data can be sent and received synchronized in both directions.

BTW .. WC is not supported by the Digiface USB
and  to make a preamp clock master is possible, but not the best solution, because:
a) Digiface USB might have better clock
b) What if you connect 2 or more preamps ?! 1 would be clock master, the other still wouldn't get a clock signal
c) You loose the possibility that the application/DAW is able to set the sample rate for your environment, this is only possible if the Digiface USB is clock master and the Preamps connected to it clock slaves.

As not all preamps have a digital input you need to check carefully whether the Digiface USB is well suited for your environment or whether the RayDAT would be better as an optional WC module is available.

From manual: Another common source of trouble is incorrect synchronization. ASIO does not support asynchronous operation, which means that the input and output signals not only have to use the same sample frequency, but also have to be in sync. All devices connected to the Digiface USB must be properly configured for Full Duplex operation. As long as SyncCheck (in the Settings dialog) only displays Lock instead of Sync, the devices have not been set up properly!

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14
  • From: Sweden
  • Registered: 2013-12-25
  • Posts: 190

Re: Periodic pops from Digiface USB's ADAT output?

Do you have the focusrite connected via usb to the computer at all times? When I had an RME UCX and a Steinberg ur 824 in much the same fashion as you have the digiface and 18i8, keeping the steinberg connected to the computer messed things up, perhaps the solution is as simple as that?

Babyface Pro FS, MSI GS66, Studio One

8 Reply by cjunekim (edited by cjunekim 2021-01-18 07:56:14)

  • Registered: 2021-01-17
  • Posts: 30

Re: Periodic pops from Digiface USB's ADAT output?

ramses wrote:

I think this is meant by full-duplex operation, that there is a digital connection in both direction
and that data can be sent and received synchronized in both directions.

My understanding is this. If you want to add an input device(mic preamp for example) and use it as a slave at the same time, you need two ADAT connections. One for receiving the input signals from the preamp to digiface and another for sending clocking signals from digiface to the preamp.

However, if you are going to use digiface as master with another output device only, you need to connect a single ADAT cable. Because that single connection will convey audio signal and clock signal altogether. Hence, no need for full duplex connection in this case. That's right?

  • Registered: 2021-01-17
  • Posts: 30

Re: Periodic pops from Digiface USB's ADAT output?

ebmmbongo wrote:

Do you have the focusrite connected via usb to the computer at all times? When I had an RME UCX and a Steinberg ur 824 in much the same fashion as you have the digiface and 18i8, keeping the steinberg connected to the computer messed things up, perhaps the solution is as simple as that?

Yeah. 18i8 is connected to the computer always. I use 18i8 as a usb interface occasionally so it has to be that way.

So you use UR824 in the standalone mode?

  • Registered: 2021-01-17
  • Posts: 30

Re: Periodic pops from Digiface USB's ADAT output?

So I've been doing continuous experimentation for a day or two and now the pop and crackling noise is gone, fortunately.

Firstly, I changed the usb devices here and there. But I'm pretty sure this didn't affect anything, since I tested in the best possible setting(18i8 alone on a host controller and digiface alone on another host controller, which has Message Signaled-Based Interrupts mode supported) and it still made noises.

Then I added ADAT input to digiface. 18i8's coax digital out to Coax-to-spdif converter to digiface. But 18i8 is still a slave, and shown as SYNC in Input Status of MADIface Series Settings window.

Also reconnected all the optical cables with different arrangement.

I'll see if it keeps working for a few days.

  • Registered: 2021-01-17
  • Posts: 30

Re: Periodic pops from Digiface USB's ADAT output?

Now they are working okay, so I have no chance to test your suggestions. But they seem to be useful tests that I might have tried.

BTW, on the 3rd test, USB Tree View doesn't continously access USB devices. It uses OS's detect notification of removal or adding, AFAIK. Additionally, I heard noises when there was nothing running on the OS. Thanks anyway.

MetalHeadKeys wrote:

Thanks for the info!!

Time to troubleshoot!! smile

1st Test:

This is rather obvious, but just for the sake of it, unplug the Focusrite from usb and optical connection.
Plug a pair of headphones in the DigiFace USB and check for any popping audio.
I don't think you will hear anything, because it would have been recorded in your DAW, when you checked the first time.

2nd Test:

Re-connect the Focusrite with the DF Usb via optical, and also, connect it to its USB Port.
Save the Focusrite Mixer Routing on it, disconnect it from Usb and check if you have audible pops(Focusrite stand-alone operation) from your monitors.

If you do hear pops, proceed to:
3rd Test:

I think the real suspect is the UsbTreeView App that you are using.
And this feature, in particular:

Safe removal, device restart and port restart

from this page: https://www.uwe-sieber.de/usbtreeview_e.html

I think that it's, continuously, monitoring the Usb Port and somehow messes with the Usb controller and its power settings.

So, I 'd suggest to disable the App or uninstall it, connect the DigiFace to a port that's coming directly from the MoBo's Cihipset,
and then go to:
Device manager -> Usb controllers -> Usb Hubs -> Right click on the one the DF Usb is connected to -> Properties -> Power Management -> UnCheck the "Allow windows to turn off this device" Option.

Waiting for update!

  • ramses
  • DAW Mastermind
  • Offline
  • From: UTC+1
  • Registered: 2012-10-14
  • Posts: 13,161

Re: Periodic pops from Digiface USB's ADAT output?

cjunekim wrote:
ramses wrote:

I think this is meant by full-duplex operation, that there is a digital connection in both direction
and that data can be sent and received synchronized in both directions.

My understanding is this. If you want to add an input device(mic preamp for example) and use it as a slave at the same time, you need two ADAT connections. One for receiving the input signals from the preamp to digiface and another for sending clocking signals from digiface to the preamp.

However, if you are going to use digiface as master with another output device only, you need to connect a single ADAT cable. Because that single connection will convey audio signal and clock signal altogether. Hence, no need for full duplex connection in this case. That's right?

Clock signals from recording interface to the preamp can only be transferred into the sending direction.
So it is not sufficient to connect a preamp only by one TOSLINK cable.
or you would need to use WC (not possible as Digiface USB doesn't offer WC)
or you would need to use e.g. Preamp1 as clock master if the other preamps have at least one digital input like ADAT.

The two possibilities:

Digiface USB as Clock Master for all connected devices:

Digiface USB - ADAT1 IN    <------------ simply audio ---------------- ADAT OUT Preamp1
Digiface USB - ADAT1 OUT ------------ audio and clock --------------> ADAT IN  Preamp1
[...]
Digiface USB - ADAT4 IN    <------------ simply audio ---------------- ADAT OUT Preamp4
Digiface USB - ADAT4 OUT ------------ audio and clock --------------> ADAT IN  Preamp4

One external device - Preamp 1 - as clock master:

Digiface USB - ADAT1 IN    <------------ audio and clock  ---------------- ADAT OUT Preamp1
Digiface USB
Digiface USB - ADAT2 IN    <------------ simply audio ---------------- ADAT OUT Preamp2
Digiface USB - ADAT2 OUT ------------ audio and clock --------------> ADAT IN  Preamp2
[...]
Digiface USB - ADAT4 IN    <------------ simply audio ---------------- ADAT OUT Preamp4
Digiface USB - ADAT4 OUT ------------ audio and clock --------------> ADAT IN  Preamp4

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14
  • Registered: 2021-01-17
  • Posts: 30

Re: Periodic pops from Digiface USB's ADAT output?

ramses wrote:

Clock signals from recording interface to the preamp can only be transferred into the sending direction.
So it is not sufficient to connect a preamp only by one TOSLINK cable.
or you would need to use WC (not possible as Digiface USB doesn't offer WC)
or you would need to use e.g. Preamp1 as clock master if the other preamps have at least one digital input like ADAT.

Oh, I meant, in the case of using one output device(DA converter) with digiface, you need just a single ADAT connection if you are using digiface as master, since it will convey audio and clock signal altogether. Right?

  • From: Sweden
  • Registered: 2013-12-25
  • Posts: 190

Re: Periodic pops from Digiface USB's ADAT output?

cjunekim wrote:
ebmmbongo wrote:

Do you have the focusrite connected via usb to the computer at all times? When I had an RME UCX and a Steinberg ur 824 in much the same fashion as you have the digiface and 18i8, keeping the steinberg connected to the computer messed things up, perhaps the solution is as simple as that?

Yeah. 18i8 is connected to the computer always. I use 18i8 as a usb interface occasionally so it has to be that way.

So you use UR824 in the standalone mode?

Yes I did, but I used it for both in- and output (I think you use the focusrite for outputs only?).
Can you try and see if disconnecting the focusrite solves the issue?

Babyface Pro FS, MSI GS66, Studio One
  • ramses
  • DAW Mastermind
  • Offline
  • From: UTC+1
  • Registered: 2012-10-14
  • Posts: 13,161

Re: Periodic pops from Digiface USB's ADAT output?

cjunekim wrote:
ramses wrote:

Clock signals from recording interface to the preamp can only be transferred into the sending direction.
So it is not sufficient to connect a preamp only by one TOSLINK cable.
or you would need to use WC (not possible as Digiface USB doesn't offer WC)
or you would need to use e.g. Preamp1 as clock master if the other preamps have at least one digital input like ADAT.

Oh, I meant, in the case of using one output device(DA converter) with digiface, you need just a single ADAT connection if you are using digiface as master, since it will convey audio and clock signal altogether. Right?

Oh, did I misunderstand ?
Yes you are correct. If you connect e.g. only a D/A converter then this is sufficient:

Digiface USB (clock master) - ADAT1 OUT ------------ audio and clock --------------> ADAT IN  D/A converter

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14
  • Registered: 2019-10-01
  • Posts: 675

Re: Periodic pops from Digiface USB's ADAT output?

cjunekim wrote:

Now they are working okay, so I have no chance to test your suggestions. But they seem to be useful tests that I might have tried.

BTW, on the 3rd test, USB Tree View doesn't continously access USB devices. It uses OS's detect notification of removal or adding, AFAIK. Additionally, I heard noises when there was nothing running on the OS. Thanks anyway.

MetalHeadKeys wrote:

Thanks for the info!!

Time to troubleshoot!! smile

1st Test:

This is rather obvious, but just for the sake of it, unplug the Focusrite from usb and optical connection.
Plug a pair of headphones in the DigiFace USB and check for any popping audio.
I don't think you will hear anything, because it would have been recorded in your DAW, when you checked the first time.

2nd Test:

Re-connect the Focusrite with the DF Usb via optical, and also, connect it to its USB Port.
Save the Focusrite Mixer Routing on it, disconnect it from Usb and check if you have audible pops(Focusrite stand-alone operation) from your monitors.

If you do hear pops, proceed to:
3rd Test:

I think the real suspect is the UsbTreeView App that you are using.
And this feature, in particular:

Safe removal, device restart and port restart

from this page: https://www.uwe-sieber.de/usbtreeview_e.html

I think that it's, continuously, monitoring the Usb Port and somehow messes with the Usb controller and its power settings.

So, I 'd suggest to disable the App or uninstall it, connect the DigiFace to a port that's coming directly from the MoBo's Cihipset,
and then go to:
Device manager -> Usb controllers -> Usb Hubs -> Right click on the one the DF Usb is connected to -> Properties -> Power Management -> UnCheck the "Allow windows to turn off this device" Option.

Waiting for update!

You 're welcome!

About the UsbTreeView, I thought it was an app running in the background. But I didn't delve on the site to check that out!
Anyway, glad that you sorted it out!!

RME Gear: Digiface USB, HDSP 9632