Hi Ben,
Thanks for reaching Roon support — we found several things worth addressing. Here’s what the logs show, in order of impact:
1. Cambridge Audio DacMagic 200M 2.0 — repeated USB disconnects (root cause of DSD/audio issues)
This is the most significant finding. The system logs show the DacMagic has been physically disconnecting and reconnecting from the Nucleus USB port over a dozen times since the last reboot on May 28 — roughly every few hours. Each disconnect forces the Roon audio engine to reinitialize, which will interrupt or stutter any playback in progress.
On June 5 specifically, it reconnected at 9:19 PM — about 10 minutes before your main incident window. This caused the local RAAT audio server to restart at 9:23 PM, which cascaded into the broader disruption you experienced.
Actions to try:
- Try a different USB cable between the Nucleus and the DacMagic
- Try a different USB port on the Nucleus One
- Check whether the DacMagic has any USB power-save or auto-sleep mode in its settings and disable it
- If the issue continues, a powered USB hub between the Nucleus and DacMagic can help provide more stable power
2. ARC — UPnP port mapping unavailable on Meraki Go (root cause of ARC connectivity)
Every time Roon checks its ARC connectivity (every few hours), it fails to find a UPnP or NAT-PMP capable router:
Error: [mobile] [multinat] Timeout waiting for UPnP response.
Error: [mobile] [multinat] No UPnP Router found! Exiting
The Meraki Go firewall does not support UPnP or NAT-PMP, so Roon cannot automatically configure port forwarding. ARC is falling back to Roon’s relay servers, which is less reliable than a direct connection and explains why ARC is intermittently unavailable.
Fix: Manually configure a port forwarding rule on the Meraki Go for TCP port 55000 pointing to the Nucleus at 192.168.0.240. Once that’s in place, ARC will have a stable direct connection. Also confirm that 192.168.0.240 is either a static IP on the Nucleus or a permanent DHCP reservation on the Meraki (you mentioned you need to double-check this — it’s important that the Nucleus always gets the same IP).
3. Remote/controller lag — iPhone Wi-Fi keep-alive timeouts
Around 9:30 PM on June 5, the Roon server repeatedly lost its connection to the Roon app on one iPhone (192.168.0.187) with:
[rnet/RnetJsonClient] no data received for >10000ms. Killing connection.
This fired every ~10 seconds for several minutes. The device was immediately reachable again on each reconnect, which rules out a switch or general network problem — this is the phone’s Wi-Fi going quiet while the app is in the foreground (or transitioning to background). The iPad (192.168.0.75) also showed “Connection refused” after the 9:23 PM RAAT restart, suggesting the Roon app on the iPad had been backgrounded or killed.
These repeated reconnections are what caused the multi-remote lag — the controllers were repeatedly losing and re-establishing their connection to the Nucleus. iOS aggressively limits network activity for background apps. Make sure the Roon app is fully in the foreground on your remotes during listening sessions, and check that Low Power Mode is off on those devices.
4. DNS — configured at router, not 8.8.8.8 directly
The Nucleus’s resolv.conf shows 192.168.0.1 (your Meraki) as the DNS resolver, not 8.8.8.8 directly. This is normal — RoonOS uses DHCP-provided DNS, and your Meraki is acting as the DNS forwarder. As long as the Meraki is forwarding upstream to 8.8.8.8/8.8.4.4 (which you’ve configured on it), DNS should work fine. We don’t see DNS resolution failures in the logs.
Summary of actions:
| Priority |
Action |
| 1 |
Swap the DacMagic USB cable; try a different Nucleus USB port |
| 2 |
Set up manual port forward: TCP 55000 → 192.168.0.240 on Meraki Go |
| 3 |
Set a static DHCP reservation for the Nucleus |
The intermittent nature of your issues is consistent with the USB instability — when the DacMagic drops and reconnects, it disrupts the RAAT session and affects remote responsiveness. Stabilizing the USB connection should resolve most of what you experienced. Let us know how it goes after swapping the cable.
