· Chromecast devices are no longer showing up on my audio device list. I have been trialing Roon for ~3 days and the first 1.5 days I had no issue seeing each of my Chromecast devices (a mix of Nest Hub Max and Nest Hub speakers). Then, on day 2, they disappeared. I tried restarting the Roon app that was acting as a server and it fixed the problem once. They reappeared. But now, on day 3, when I checked again, they were again missing. I have restarted the app several times and have had no luck. The Roon server is an old MacBook Pro, MacOS 12.7.6 connected to my router by wire. I checked and all Chromecast devices are on the same subnet. All are pingable by the MBP. All are discoverable in the Google Home app on my phone. They simply are no longer discoverable by the Roon server. What should my next troubleshooting steps be?
Tell us about your home network
· TP-Link Archer BE800 router. Roon server on MacBook Pro connected by ethernet. Google Chromecast devices connected by 5GHz Wi-Fi. All on the same subnet.
Thanks for writing in and thanks for all the information you’ve provided!
I know you mentioned all the chromecast deivces appear to be on the same subnet - that is good news! Is there a chance the Mac running Roon Server could be on a different subnet? Or, even being exposed to multiple subnets may be causing it to have difficulty communicating with your chromecast devices within Roon.
If possible, temporarily, test out disabling all but a single subnet within your local network - reboot your router, and let us know if that changes any of the behavior.
We want to make sure you have ample time to test Roon without issues - let us know how the above goes and we’ll be on standby for your reply. Thank you!
Sorry that my explanation was not clear. I meant that the devices are all on the same subnet as the MBP running the Roon server. This has been the case the entire time. I just checked again and still I see none of the Chromecast devices in the Roon app. I tried resetting each of the devices and my router and still no luck.
Thanks for the additional information! Have you also checked the firewall settings within the Mac running Roon Server?
The easiest way to test this would be to temporarily disable your macOS firewall, and reboot the machine. Then, log into Roon and see if your devices pop up properly.
I tried already before to disable the macOS firewall and didn’t see any improvement. I just tried again and rebooted the computer as suggested. I still don’t see the devices.
Thanks for the additional information - I’m so sorry you’re still running into issues here!
I’ve updated your thread to be private, just between you and the Roon team. From your Roon Server diagnostics, I’m seeing a few things network-related that I beleive is worth sharing.
First, we’re seeing two reported IPs for your Mac running Roon Server:
192.168.0.yyy
and
100.80.243.yy
With that, I actually see your Chromecast devices being active and connected to your server just a few minutes ago, with the following IPs:
Chromecast: Google Nest Hub
IPs - 192.168.0.142
--
Chromecast: Google Nest Hub Max
IPs - 192.168.0.150
--
Chromecast: Google Nest Hub Max
IPs - 192.168.0.127
--
Chromecast: Google Nest Hub
IPs - 192.168.0.165
--
Chromecast: Google TV Streamer
IPs - 192.168.0.149
Are you still running into issues here?
With that, I do see that you have a second Mac machine running as a Roon remote - as a quick side test, if you temporarily set this other Mac to run as your Roon Server, are you able to see and enable your chromecast devices?
First, I also briefly saw the devices yesterday but then they disappeared again.
The other IP was a Tailscale server that I was running to be able to access files on my old MBP from an iPad while traveling. I haven’t used it in a while so I’ve disabled it in case it’s causing any of the issues.
I did as you suggested and switched to my primary Mac (the second Mac you mentioned) as Roon server temporarily and indeed I immediately saw the missing Chromecast devices. I then switched back to the Mac I intend to use as a server and as of now I am still seeing the Chromecast devices. This is exactly how my trial started, though. I set up the server, saw the devices, enabled them, and things were fine for a day or so.
I can keep evaluating to see if the devices persist or if they drop off again. Perhaps the Tailscale server had something to do with it…
Sadly, I’m seeing the same problem as before. I still have MacOS firewall off and I completely removed the Tailscale server. After letting the Roon server run for ~a day, I checked again and all the Chromecast devices were gone.
I once again switched my other computer to be the Roon server and immediately see the devices. I switched back to the one I want to use as a server and the devices are present again. But I am confident they will eventually disappear.
Any other thoughts as to what the root cause of this could be?
Ah, I’m sorry to hear that! We were able to pinpoint the failure point with a fresh Roon Server diagnostic report and see the following:
[cast] lost device CastDevice[...] because we got a TTL=0 mDNS packet
A TTL=0 mDNS packet is an explicit “This service is no longer available on the network” and when Roon receives that, it must immediately remove the device from the available audio endpoints list.
TTL=0 packets often appear when:
IGMP snooping is broken or misconfigured
Multicast is rate-limited or dropped by the router/AP
Mesh Wi-Fi nodes reshuffle clients
“Multicast enhancement”, “Airtime fairness”, or “Smart connect” features interfere
VLANs or AP isolation partially block mDNS
In these cases, the device may still be online, but the mDNS state machine collapses and resets.
We then quickly see:
unexpected KeyNotFoundException error in device data: ... key md
This indicates the Nest Hub is advertising incomplete or malformed Cast metadata.
This usually happens during device transitions (restart, reconnect, firmware swap), reinforcing that the device is not cleanly re-announcing itself.