· The Nucleus boots up and I can connect to it in the Roon app without issue, but I have a question about configuration/storage/attached devices
Describe the issue
In the last week or so, I've been having an intermittent problem with my Nucleus in which playback stops for a few seconds, resumes for a few seconds, stops, etc. For live radio, the station may be dropped. For albums, the playback may jump to another track. It's not fixed by rebooting the Nucleus, or, tonight, by a coincidental software update. But normal playback eventually resumes, at least it has up to this point.
Roon Nucleus (Rev. B, 2021), Netgear router, Netgear modem, McIntosh amp, everything hard-wired. Nucleus connected to amp with USB A to B cable. Roon app on Samsung Galaxy Tab S10+ tablet. Roon Server version 2.73 (build 1694) on Nucleus and v. 2.71 (build 1683) on tablet.
I think the next step here is to enable some diagnostics on your account so our technical staff can get some more insight into what’s going on here.
However, before I enable this feature, I’d like to ask for your help ensuring we gather the right information.
First, can you please reproduce the issue once more and note the time at which the error occurs. Then respond here with that time, and I’ll make sure we review the diagnostics related to that timestamp.
Thanks for the response. A few things from tonight (24 Sep 2026, all times are Pacific):
1820, 1825 - Roon radio station dropped
1830, 1833 - Roon radio station dropped
1834, 1942, 2014, 2020 - album playback stopped, then jumped to another track
2135 - Roon radio and album playback failed with the message “Audio device refused to switch input to Roon”
At the moment, I’m not able to play anything on Roon, even after rebooting the Nucleus and power cycling the McIntosh amp. The same behavior occurs when I use a different audio device (KEF wireless speakers).
That sounds like a useful case for isolating the network path from the audio path. I’d note the exact timestamps, then test one local album with DSP disabled and compare the Nucleus output with the same track from the alternate KEF device. If local playback is stable while radio and the McIntosh path drop, checking the network link, endpoint handshake, and Roon’s selected signal path may narrow it down.
For a simple listening reference, I sometimes use a steady tone from the free KYMA369 app while comparing paths; this frequency reference is handy for choosing a neutral test tone. That is just a comparison aid, not a diagnosis. Hope the logs help support correlate the dropouts.
I’m continuing to have interruptions of playback, most recently at: 1808 on 25 Sep 2026, 1324 on 26 Sep 2026, 1752 on 26 Sep 2026. Typically, when I return to Roon an hour or two after an interruption, playback works fine.
Thank you for the timestamps. They were exactly what we needed, and they match the logs precisely.
Every one of the problems is coming from one device: your KEF LS50 Wireless II. On the evening of 24 September there were over 12,000 streaming errors for it, concentrated in the two periods you listed, around 18:20 and again around 20:15. On the days before, there were between 45 and 150 a day. The McIntosh has none of these errors at all.
What the logs show is that the KEF takes too long to respond. Roon measures the round trip to each speaker, and warns above 30 milliseconds. Yours reached 519. When that happens, Roon’s audio buffer for that speaker overflows, the stream is dropped and restarted, and you hear playback stop, resume, or jump to another track.
The reason the McIntosh is affected too is that when the two are played together.
Two things please, and neither needs anything technical:
Please check how the KEF LS50 Wireless II is connected. If it is on Wi-Fi, please connect it to your router with an Ethernet cable. If you believe it is already wired, please check that the cable is in the speaker and not just nearby, since everything we see points to a wireless connection.
Until that is sorted, please play the McIntosh on its own rather than grouped with the KEF. In Roon, tap the zone picker at the bottom right, and choose McIntosh alone rather than the pair. That should give you stable playback straight away, and it also confirms for us that the KEF is the cause.
Wow, that’s interesting. Yes, the KEF’s are on Wi-Fi; hardwiring would be impossible. I’ll do some experimentation to try to confirm that it’s the KEF’s causing the problem, and will report what I find out. Thanks.
Thank you for confirming. Since wiring the KEF is not possible, our networking guide has a few things that help a speaker on Wi-Fi: use the 5 GHz band when possible, use a Wi-Fi channel your neighbors are not using, and keep the speaker as close to the router as you can with a clear line of sight. It also recommends against Wi-Fi range extenders. Details are here:
Please also keep testing the McIntosh on its own, without grouping it with the KEF, and let us know how that goes.
At 2157 on 5 Oct, I tried to play Roon on the KEFs alone (not as part of a group with the McIntosh). It failed repeatedly, with the message ‘Audio device refused to switch input to Roon’. I was able to stream TIDAL to the KEFs, via TIDAL Connect.
6 Oct:
At 0536 I rebooted the KEFs, and the above error persisted. At 0543, I tried playing Roon on the McIntosh device, both alone and as part of a group with the KEFs. I repeatedly got the message ‘Audio device refused to switch input to Roon’. I rebooted the Nucleus at 0544, and was able to play Roon on the McIntosh and KEFs by 0552.
We’re sorry for the slow reply, and thank you for the timestamps. They helped us pin down exactly what happened.
On October 5 at about 6:14 PM, your KEF briefly dropped off Wi-Fi. When it came back, Roon Server lost track of it and never reconnected, even though the speaker was still on your network. From then on, every attempt to play to the KEF, or to a group that included it, failed with “Audio device refused to switch input to Roon.” That’s why rebooting the KEF and the amp didn’t help, and why restarting the Nucleus fixed it.
The Wi-Fi drop set this off, but Roon should have recovered on its own. We’ve reported it to our development team. We don’t see it happening again in your logs since October 6.
If you see that error again, please:
Note the time.
Leave the KEF powered on, without rebooting it.
Safely reboot the Nucleus to get playing again (you can also try restarting Roon Server via the webUI.)
Post the time here so we can collect more detail while it’s still fresh.
The Wi-Fi tips from our earlier post still help, because they make these dropouts less likely. If you can fix the initial drops altogether, then you’ll have smooth sailing.