USB Speaker Not Detected by Roon Due to Communication Issue with Roon Server (ref#YUTKSG)

Support
1

What best describes your playback issue?

· A connected audio device is not appearing in Roon

What type of Zone is affected by this problem?

· *Directly-connected Zones* are affected.

Is your RoonServer machine running MacOS 15 Sequoia or above?

· I still can't see my endpoints as available Zones.

Is the affected network Zone connected with Ethernet or WiFi?

· Ethernet

Which network audio protocol is the Zone using with Roon?

· RoonReady

Does the device show up at all in Roon Settings -> Audio?

· No, it does not show up there

Does the device play audio from another source when using the same connection?

· The device has no problems with another audio source

Have you checked that Roon is whitelisted in any firewalls?

· I've checked the firewall and the issue remains

Since you are using a network connection to the device, please ensure that your RoonServer is on the same subnet as the device

· My devices are on a single subnet but is not visible to Roon

Do you have a complex network setup?

· Both the device and RoonServer are connecting to a *single router*

Try to disable any additional networking interfaces on your RoonServer machine.

· Disabling network interfaces had no change in behavior

Check to make sure RoonReady mode is selected on the device.

· I've checked this and the issue remains

If the device has multiple output options, do the other options work as expected?

· Only one output type is affected while the other output type works as expected

Is the device using the latest firmware as per the manufacturer?

· Firmware is up-to-date but the issue remains

What are the make and model of the affected audio device(s) and the connection type?

· Vanatoo Transparent Zero connected via USB

Describe the issue

Attached usb speaker not appearing in roon. diagnosed comm problem with roon server

Describe your network setup

12:43 PST 5/31/2026

2

Windows 10 machine S20 (192.168.1.120) running Roon Server.
Windows 11 machine S22 (`192.168.1.17) running Roon.
S22 has a USB speaker by Vanatoo that never shows up in the audio endpoint list.

I’ve diagnosed it as follows:

The specific bug is: SOOD on S22 broadcasts on both the real NIC and loopback, and S20’s Roon Server consistently picks up the loopback address first and never falls back to the real IP.

The key facts are:

  • S22 RAATServer correctly binds to 192.168.1.174 but SOOD also binds to 127.0.0.1

  • S20 RoonServer discovers S22 as 127.0.0.1:9200 and fails to connect

  • TCP connectivity from S20 to S22 192.168.1.174:9200 works fine (confirmed via Test-NetConnection)

  • Fresh install of Roon on S22 did not resolve it

  • The loopback binding appears to be caused by the “Ethernet (Kernel Debugger)” adapter present on S22

Note: Kernel Debugger adapter running — it’s unusual and likely the root cause of SOOD binding to loopback. S22 has kernel debugging enabled (bcdedit shows debug=Yes) and has an ‘Ethernet (Kernel Debugger)’ network adapter visible in the system. I cannot disable it due to Secure Boot policy. We believe this may be causing SOOD to bind to the loopback interface in addition to the real NIC.

3

Hello @Alan_Watkins ,

Thanks for reaching out, and your patience as we reached your case.

When you reinstalled, did you also set the previous Roon database aside? You can also try to reinstall RAATServer, this is the mechanism that manages the local audio endpoint list. You can do both by following these steps on the affected machine:

  • Create a Backup of your current Roon database
  • Exit out of Roon
  • Navigate to your Roon’s Database Location
  • Find the folder that says “Roon” and “RAATServer”
  • Rename “Roon” to “Roon_old” and “RAATServer” to “RAATServer_old”
  • Reinstall Roon from our Downloads Page

Did you by any chance clone these two machines or restore whole disk backups to one another?

4

If by Roon Database you mean the one holding all the recording data, no I have neither deleted it nor copied it since Room Server was first installed on S20.

In the process of debugging, RAAT server was reinstalled many times However, I will do as you suggest. To be clear about which is which, S20 runs roon server. S22 runs Roon application and has the missing audio devices. Which do you want me to do this on?

Neither machine has been restored from an image backup or anything like it, ever, if that’s what you mean by clone. S22, to the best of my knowledge has never run Roon Server, unless accidentally which I might not remeber. S20 first got Roon server well after S22 was commissioned.

5

Hi @Alan_Watkins,

Thank you for the clarification. Please perform the steps on both machines to be thorough:

On S22 (Roon Remote + audio device):

  1. Exit Roon

  2. Navigate to the Roon Database Location

  3. Rename the RAATServer folder to RAATServer_old

  4. Reinstall Roon from our Downloads Page

On S20 (Roon Server):

  1. Create a Backup of your Roon database first

  2. Exit Roon Server

  3. Navigate to the Roon Database Location

  4. Rename the Roon folder to Roon_old and RAATServer folder to RAATServer_old

  5. Reinstall Roon from our Downloads Page

  6. Restore your backup when prompted

Regarding the Kernel Debugger adapter on S22 — your diagnosis is spot on. If disabling it is not possible due to Secure Boot policy, an alternative worth trying is to go to Device Manager → Network Adapters, right-click the Ethernet (Kernel Debugger) adapter, and select Disable device.

Let us know how it goes after the reinstall!

6

I tried disabling kernel debugger in DM but it did not help.

I did as instructed above. The Vanatoo speakers, after a USB unplug/plug, work as the system default in Windows, but do nto appear in Roon on S22. In addition, when I select System Output (i.e. Vanatoo) and hit play the play progress bar acts as if it is playing but there is no sound. If I switch to the Realtek built-in speakers, the progress bar does not move at all regardless of my hitting play. This differs from when I file my support request only in that playing those devices would generate a “too many errors” message, and would not play.

What next?

7

Hey @Alan_Watkins,

Thanks for the follow-up! Sorry to hear you’re still having playback issues.

From a recent Roon Server diagnostic report, we can see every attempt to play through the Realtek ASIO zone fails with the same fatal sequence:

Warn: [Realtek] [zoneplayer/raat] Failed to prepare Realtek ASIO in 15000ms. Giving up
Warn: [Realtek] [zoneplayer/raat] failed to setup any endpoints..giving up
Warn: [zone Realtek] Track Stopped Due to Error
Info: [zone Realtek] OnPlayFeedback StoppedEndOfMediaUnnatural

The Realtek ASIO driver is timing out during device preparation, it cannot open an exclusive stream. The most likely culprit is that the Vanatoo USB speakers had been unplugged and replugged, causing Windows to switch the default audio device. The Realtek ASIO driver may be trying to acquire hardware that is locked or has shifted state. The ASIO driver also has no volume control (“is_supported”:false) which compounds the issue, as Roon has no fallback.

We’re also seeing playback issues to the System Output, Roon reports this device’s supported formats as:

"supported_formats": [
 {"sample_type":"pcm","bits_per_sample":16,"sample_rate":48000,"channels":1},
 {"sample_type":"pcm","bits_per_sample":16,"sample_rate":48000,"channels":2}
]

This is extremely limited, only 16-bit/48kHz, max 2 channels. Roon is forced to do sample rate conversion on everything (e.g., 44.1kHz → 48kHz), and it can only operate in WASAPI shared mode (wasapi_shared).

This explains why playback progress shows as moving but no sound is produced: after the USB re-plug, the Windows default audio device changed to point to the Vanatoo, but the WASAPI shared mode output is routing audio to the wrong underlying endpoint, or the Vanatoo’s USB audio stack hasn’t fully initialized from Roon’s perspective.

The play bar moves because Roon thinks it’s streaming successfully, but the audio path to the speakers is broken at the OS/driver level.

It’s also important to note that the Vanatoo speakers never appear as a discrete WASAPI device, there is no entry with their USB audio name. They are only reachable through “System Output” (i.e., whatever Windows sets as the default). This means Roon has no direct device-level control over the Vanatoo, cannot see it independently, and cannot recover if the default output shifts.

Here are some next steps for you to try:

  1. In Windows Sound settings, confirm the Vanatoo is set as the default output and that it shows as "Ready" (not "Not plugged in").
  2. In Roon Settings → Audio, scroll through all WASAPI devices, the Vanatoo should appear by name if Windows has fully registered it. If it doesn't, try restarting RoonServer after the USB plug.
  3. The Realtek ASIO failures are independent and persistent, that zone will need its ASIO driver reset or the JRiver/miniDSP exclusive access conflicts resolved before it will work.
  4. The 16/48 format limitation on System Output is expected for WASAPI shared mode, this is not the cause of silence but does limit audio quality.
Hope this helps, Alan! 👍
8
  1. In Windows sound settings, Vanatoo definitely the defaults device. I do not see anywhere that would show “plugged in” or “ready”. It does of course work in the OS itself, etc. Where in Win 11 would I find that property?
  2. it does not show in Roon, and restarting Roon Server did not change that, including after restarting Roon client on S22.
  3. How do I reset the realtek ASIO driver? How do I resolve exclusive access conflicts"?
  4. Is it an issue when Vanatoo is set for 16/44 instead of 16/48, other than the need for conversion? Aside from that, with the quality of a small desktop USB speaker the resolution and sample rate are hardly issues.
9

Got it, thanks @Alan_Watkins,

If you can, since you can’t remove the Kernel Debugger adapter, try binding it to a dummy/unused IP to prevent SOOD from treating it as a valid interface:

You should be able to access in Device Manager → Network Adapters → right-click “Ethernet (Kernel Debugger)” → Properties → Internet Protocol Version 4 → assign it a static IP in an unused subnet (e.g., 10.255.255.1 / 255.255.255.0), no gateway.

This doesn’t disable it but may stop SOOD from preferring it for discovery.

Also, something to consider, as a diagnostic only: temporarily install Roon Server on S22 itself and point your Roon remote to it. If the Vanatoo then appears as a WASAPI endpoint on the local machine, it confirms the issue is 100% the cross-machine SOOD discovery failure, and not something deeper with the Vanatoo’s USB audio driver on S22.

To reset the Realtek ASIO driver and clear exclusive-mode conflicts:

  • Open Realtek Audio Console (or HD Audio Manager) → Disable "Allow exclusive mode" if enabled
  • In Windows Sound → right-click Realtek device → Properties → Advanced → uncheck "Allow applications to take exclusive control"
  • Check if JRiver or miniDSP (mentioned in the diagnostics) is running and holding the ASIO driver open, close those apps and try Roon again
  • If the ASIO driver is still broken, uninstall it from Device Manager, reboot, and let Windows reinstall the generic Realtek driver

Thanks, Alan!

10

Microsoft Kernel Debug Network Adapter properties shows only General, Driver, Details, and Events tabs and I don’t find any IP address-related properties in any of them. Does it appear on your machine?

11
  • “Allow Exclusive Mode” does not appear in Realtek Audio Console.
  • I unchecked “Allow applications to take exclusive control” in Sound>Playback>Speakers (Realtek)>Advanced.
  • Neither Jriver nor miniDSP has been running through any of this effort.
12
  • I reinstalled the Realtek driver under Sound, Video and Game Controllers, getting the Microsoft version. With the Realtek audio device selected in Roon playing music causes nothing to happen. The progress bar remains at zero.
13

I ran RoonServer on S22 and Roon client Setting> Audio was no different. However you said “point your Roon remote to it” When you say “roon remote” do you mean say iPad Roon and then do something with it?