I don’t have an HDMI cable long enough to reach from my Nucleus to my TV. The whole system is installed in built-ins around and above my fireplace, and isn’t moveable. I could order a longer HDMI cable, but it wouldn’t come for a few days
My DAC does my volume control, via its remote. I have checked that the volume is neither too low nor too high, and the DAC is not muted.
Clicking identify for the DAC returns either DAC1 or DAC HGC, neither of which is correct. It’s actually a Benchmark DAC 3L, which doesn’t come up, but the Benchmark people say it is fine that it shows as Benchmark DAC2 USB Audio 2.0. That has worked fine for over two years since I bought the DAC, until sound stopped working several weeks ago with absolutely no changes by me.
My problem remains: the Roon App previously started not playing tracks and giving the error message “Too many failures, stopping playback”. After I double-checked that the DAC was set to USB 2.0–which it always showed—the error message went away, and the Roon App started showing that a track is playing, but there is still no sound. THAT is the problem
I described all that in greater detail earlier in this chain of posts, and in support request REF3281DK, which I put in over two weeks ago when the stopping playback error message was occurring, but to which I have never received any reply from tech support
I believe I’m understanding you to say don’t worry about the ::ffff: in the IP address of the Nucleus. OK - but what do I do to get sound from Roon?
As previously posted, Roon will play sound over my second audio zone, the AudioEngine speakers connected to my desktop (see the screenshot above). But it will NOT play sound over my Benchmark DAC audio zone. I don’t know how to erase that zone and recreate it in case it somehow has gotten corrupted - can you advise on that?
Hey @David_Taylor,
Thanks for writing in and providing such a detailed report! You have my sincerest apologies for the long delay you experienced in getting a reply from Roon support. Thank you @Rugby and @AMT for the troubleshooting thoughts provided so far!
David, as a quick follow-up test - what happens if you change your Zone Settings>Device Setup> from Device Volume to Fixed Volume? Do you experience the same issue?
I’ll be on standby for your reply 
Just saw this. No luck - when I change device setup to fixed volume, Roon still shows the track playing but there is no sound
How exactly did you check that? To me it looks like the only change happened when you manipulated the DAC which would make the whole issue a DAC issue then. Did you try and disconnect/reconnect the USB cable? Could it possibly be a cable/interconnect problem? If not then it might as well be the DAC. Can you possibly test the DAC’s proper functionality by using another source and cable then what’s currently in use?
Note: Even electronic components and circuitry ages over time and at some point may start to fail. I just got rid of some fancy lifestyle smart speaker and streamer (same brand and age) that stopped working and were too old and cheap to even try and get repaired. Also the streaming/USB boards inside a DAC are often third-party add-on boards that not necessarily follow the high standards set by the product they got added to. A replacement of the board may be what’s needed to fix your issue.
Hi, BlackJack. Thanks for the note. As I noted earlier in this thread, I disconnected and reconnected the USB cable, and also substituted a different USB cable in case something had gone funny with the one in places. The DAC always showed as in USB 2.0, but at the suggestion of Rugby a week ago, I followed the directions in the Benchmark DAC manual to set the DAC to USB 2.0, just to be sure something hadn’t changed. The lights showed no change and confirmed USB 2.0, which also shows in the Roon App. Also as noted earlier, I connected my laptop to the DAC via USB, and played a CD from the laptop with no issues - so I don’t think there is any problem with the Benchmark DAC and amplifier. I did that in consultation with and at the suggestion of Benchmark’s support folks, and they also think there’s nothing wrong with the DAC and that some setting in Roon must have gotten off. The fact noted earlier that Roon can play through the DAC to my second audio zone, my AudioEngine desktop speakers, also says the DAC is fine.
My Benchmark DAC is one of the finest on the market, and is less than three years old. The Benchmark DAC 3L uses four balanced 32-bit SABRE-PRO D/A converters. I doubt that its internal hardware is the issue. Since it will play just fine to my second audio zone, I don’t see how that can be the issue.
I don’t actually know for sure that my double-checking that the DAC was set to USB 2.0 is what stopped the “stopping playback” error message. That happened after I double-checked USB 2.0, but of course post hoc ergo propter hoc is a logical fallacy 
Yes that is correct. Roon OS is not the same as Roon and there is no Roon OS 2.0 available.
I bought a new USB-A to USB-B cable today. I just used it to connect my laptop to which has Roon on it, to my Benchmark DAC. The laptop accesses my Nucleus over my network via WiFi. When the laptop is connected to my DAC via USB, Roon plays music from my Nucleus over my Benchmark DAC and amp and my main speakers just fine, both when selected on the Roon laptop and when selected by the Roon app on my iPad.
But when I use the same new USB cable to connect the Nucleus to the DAC—which is my normal setup that has worked for over two years until this problem suddenly arose without any changes to my setup—the iPad Roon app shows a track playing but there is no sound.
The problem is clearly there, with Roon and/or the Nucleus, not with my DAC, amp, or speakers. But I cannot see what causes the problem or see how to fix it. Any suggestions welcome!
While you looked extensively at the DAC side and the USB cable … as every cable has two sides, what about the NUC side? IIRC there should be at least two USB ports. Did you try to use the other one for once?
Good idea. I just tried it. Alas, still no sound 
Out of curiosity: Can you posted a picture of Roon’s signal path when playing a file without sound?