USB DAC connected to Core suddenly not detected

Hi @support,

I appear to be having a similar issue to the one reported here

My Roon Core is a headless Win 10 1709 desktop machine which has Core i7, 16GB RAM and 128 GB SSD. It has been running Roon happily for months.

Recently I moved an old Fiio E7 USB DAC and connected it to the Core, it worked fine connected to the Core and driving and old set of desktop speakers in my Study.

Today out of the blue it disappeared from within Roon completely. No matter what I do I cannot get it to pick up the DAC now. I have rebooted the Core, restarted RoonServer, attached the DAC to a new USB port. I have changed the Windows Firewall settings as discussed in the linked article above. Nothing I do seems to make any difference.

The DAC is still visible and accessible in Windows, and can been seen in Device Manager as working properly.

Please are you able to help?

@support typically I just rebooted the core again for a different reason, and the DAC is back… weird!

There might have been a Windows Update. That sometimes causes weird glitches.

Yeah I wasn’t aware of one, but something strange happened!

And… my DAC has disappeared again :frowning:

@support is there anything you can do that would help with diagnosing this intermittent issue please?

Looking at my Roon server logs I can see it discover both the System Output and the WASAPI driver. But its like the USB DAC device just isn’t picked up at all. Its not even enumerated with an error, just nothing.

In Windows the device is setup and working as expected in Device Manager.

Hmm I think I might have an idea about the cause of this actually @support It could be a bug??

My Core machine is headless, and when I log in to it via RDP is creates a ‘Remote Audio’ device. Immediately as that happens the Roon controller I am looking at loses the other devices attached to the Core including my USB DAC, and the disabled ones like WASAPI and the Realtek HD Audio Output.

It requires a reboot to bring it back, and to then never login via RDP!

Yes, RDP can cause issues. I always use teamviewer. Its free for personal use.

Hi @Tim_Rhodes ----- Thank you for the continued feedback and more importantly, thank you for your patience here. My apologies for the wait.

Moving forward, as Rugby has pointed out in his post we have indeed seen issues when a feature like Win remote desktop are used to access headless servers because it works at a pretty low level – it takes control of audio drivers, graphics drivers, network configuration, etc, and causes issues for OpenGL, which we depend on in many configurations, so we generally avoid mixing RDP and Roon when possible. Many of us use TeamViewer which is much more lightweight, have you tried giving that a shot yet to confirm if the experience is different?

Additionally, you could also configure Windows to log in automatically for your server.


Thanks @Eric I am already using the auto logon approach in Windows, but its the RDP login that causes the problem.

I’ll look into teamviewer as that seems the best alternative, or maybe Chrome RDP.

I have the same problem. Today the USB DAC (Chord Hugo TT) attached to my Windows 10 core is not available in Roon.
For info - audio is still working correctly outside of roon on this computer.

It will only be the same problem if it is caused by logging in to the Windows 10 machine using RDP. If that is the case then rebooting the machine will resolve the issue until the next time you login via RDP. This is an issue caused by the way the RDP protocol hijacks the machines audio subsystem I think.

If RDP is not a factor then you have a different issue I’m afraid.