· Hello - I just purchased a Weiss DAC 204 MK2 and connected it to my Roon Nucleus + but it does not work. I keep getting an error message that says "Too many failures. Stopping playback." After my Roon software seems to flip through a bunch of songs attempting to play them. I see from forums that people have gotten their Weiss DAC 204 to work by selecting the Weiss DAC 502 from the "Identify Device" Weiss Roon Ready menu (which does not list the 204) but that does not seem to work either. Please advise. Thank you.
Does the issue happen with local library music, streaming service music, or both?
· *Both streaming and local* *library* music are affected.
Do you encounter any playback errors with the "System Output" Zone?
· The System Output has *no problem*, it's only my other Zone.
How is the affected Zone connected to your RoonServer machine?
· Cable (USB, HDMI, SPDIF, etc.)
Is your device connected directly to the Roon Server via cable or over the network, or is it chained through another device (such as a streamer, Roon Bridge, or Roon Remote)?
· Connected directly to my RoonServer machine
Does the device show up at all in Roon Settings -> Audio?
· The Zone is listed under the wrong protocol
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
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
Do you have an approximate timestamp of when the issue last occurred?
· 2 p.m. ET Sep. 13 2026
What are the make and model of the affected audio device(s) and the connection type?
· Weiss DAC 204 MK2 connected via USB
Describe the issue
I have a brand new Weiss DAC 204 MK2 that is not working with my Nucleus+ The device is connected, seen, enabled, but music playback results in an error message that says: Too many failures. Stopping playback. This appears after the software seems to quickly try to play/skips through about 3 songs.
Describe your network setup
Verizon WiFi router connected to Eero WiFi network. Nucleus+ hardwired to Eero WiFi repeater. This setup works as all of the other Roon connected devices on my system work as they should.
Identifying it as a DAC 502 will not help, and is worth stopping. Identification only labels a device in Roon. It does not change what the device can do, and it cannot grant capabilities the hardware does not have. The DAC 204 MK2 is not among the devices we have tested and certified, which is why it is not in that list, and picking a different model from it achieves nothing.
What the logs show. Your Weiss is connected to the Nucleus by USB, not over the network. When it is plugged in, the DAC tells the Nucleus which formats it accepts, and that list includes 44.1 kHz at 24 bit. Roon then asks for exactly that, and the DAC refuses:
The same at 16 bit, and at 96 kHz. Roon retries, moves to the next track, and after enough failures you see “Too many failures. Stopping playback.”
A device that advertises a format and then declines it is in a state we cannot reach from Roon.
Worth trying first: check that the DAC’s input selector is on USB, power it off for thirty seconds and back on, and try a different USB port and cable on the Nucleus.
If that changes nothing, please take it to Weiss. The two lines above are the useful part for them, and you are welcome to quote them: the device publishes 44100/24/1|2 among its supported formats and then returns FORMAT_NOT_SUPPORTED for that same format.
Hi Vadim, Thank you for your response. I have tried the new cord, and different USB port. Can you check the logs and see if you are still seeing the same problem?
The issue does not seem to be the DAC. It works just fine using Roon from my MacBook Pro, connected directly via USB with the DAC selected as the sound output.
Yes, we are seeing the same issue with Format Not Supported in your latest diagnostics. It is rare, but it is possible that the DAC does not have compatibility with Linux.
Just to clarify, the DAC works from the Roon app when connected to the Mac, or was it through another application?
Are you using the latest firmware available for the DAC?
Is it possible there is a problem with the USB port on the Nucleus (I have tried both)? Or could there be a problem in the Roon software? Are there specific settings I should be using in the Roon software for the DAC to work?
We pulled a fresh set of logs from your Nucleus and can now see what is going wrong. We said the DAC advertises a format and then refuses it. That was wrong, which is why Weiss were able to tell you the device was fine. The audio interface opens at the format Roon asks for and then falls over for a different reason.
What actually happens is that the DAC does not answer the Nucleus in time. From the operating system:
usb 1-5: 1:1: cannot set freq 44100 (v2/v3): err -110
usb 1-5: 1:1: cannot set freq 96000 (v2/v3): err -110
usb 1-5: uac_clock_source_is_valid(): cannot get clock validity for id 41
usb 1-5: clock source 41 is not valid, cannot use
Error 110 is a timeout. The Nucleus asks the DAC to set its sample rate, a standard USB Audio request, and the DAC does not reply within the time allowed. Everything after that follows from it, including the “Too many failures” message you see in Roon. The same pattern appears even at the moment the DAC is plugged in, before any music is involved: several of its volume controls also fail to answer.
This is why it works on your MacBook. macOS is more tolerant of a device that answers slowly. It is also why changing cables and USB ports made no difference, and we should not have had you doing that.
On certification, which also answers your original question about identifying the unit as a DAC 502. The DAC 204 MK2 is not a device we have tested. The list you found is accurate, and the 204 is not on it:
. That is why it does not appear in the Identify Device menu, and why selecting a different model there changes nothing.
Our suggestion is to go back to Weiss and ask them directly about Linux support for this model. That is the right question, because the Nucleus runs Linux and the failure is in how the DAC responds to it. This is worth quoting to them:
On Linux the DAC times out on the UAC2 sample rate control request, cannot set freq 44100 (v2/v3): err -110, and subsequently fails the clock source validity read. The same unit works on macOS.
