Roon Ready devices intermittently disappearing on Mac Studio (ref#UTVE7B)

Support
1

Hi! What’s not quite right with Roon?

· None of the above quite fits

None of the above quite fits

· None of these quite match

Tell us what's going on

· Roon Ready devices appear for a few seconds and then disappear on Mac Studio

Tell us about your home network

· I have several Roon Ready devices:
* PS Audio AirLens
* dCS Network Bridge
* dCS Rossini Player
* Innuos PULSAR
* SOtM sMS-200
I also have three different Roon Core/Server machines:
* Mac mini M4
* MacBook Pro (Intel)
* Mac Studio M1 Ultra
I haven't used Roon for quite some time, and everything was working normally previously.
Today, after installing macOS 27, I started using Roon again and noticed a very strange problem.
The Mac mini and MacBook Pro work normally. All of my Roon Ready devices appear and remain available.
However, on the Mac Studio M1 Ultra, every Roon Ready device appears for approximately 5 seconds after Roon starts and then disappears. A few minutes later, they may appear again briefly and then disappear.
All three Roon Cores/Servers are on the same network and same subnet.
Troubleshooting so far
I have already:
* Uninstalled and reinstalled Roon.
* Reset my home network twice.
* Turned off the macOS firewall.
* Reset the macOS Local Network permissions for Roon/RoonServer.
* Tested both wired and Wi-Fi connections on the Mac Studio.
* Tested with my ASUS ZenWiFi BT10 network using both wired and wireless connections.
* Disabled the wired backhaul/MLO as a test.
* Enabled Multicast Routing on the ASUS router.
None of these made any difference.
An interesting test is that the Mac mini and MacBook Pro work normally on the same Wi-Fi network, while the Mac Studio still has exactly the same problem.
I also tested mDNS discovery on the Mac Studio:
dns-sd -B _roon._tcp
but it only shows:
Browsing for _roon._tcp
...STARTING...
with no Roon service appearing.
The Roon Ready devices themselves are definitely working, because they can be discovered and used by other software such as JPLAY, and they work normally when using the Mac mini or MacBook Pro as the Roon Core.
My question
Does anyone have any idea what could be causing this specifically on the Mac Studio running macOS 27?
Could this be a macOS 27 / Roon / RAAT or mDNS discovery issue specific to the Mac Studio?
Is there a way to reset or repair whatever Roon/RAAT network component is responsible for discovering and maintaining Roon Ready endpoints?
Any suggestions would be greatly appreciated.

2

Hello @mitchell_lim ,

Thank you for your message. Can you please use the directions found here and send over a set of Roon Server logs to our File Uploader? Once logs have been uploaded, please let us know so that we can check the server for your files, thanks!

3

Log file sent

4

Hello @mitchell_lim

If Roon Server runs on a Mac and your endpoints disappeared after updating to macOS 27, this is why, and here is what to do while we work on it.

macOS 27 blocks Roon Server from making outgoing connections to other devices on your network. The block happens inside the system’s network stack, before anything leaves the Mac, so Roon reports it as “No route to host”. Incoming connections are unaffected, which is why Roon itself still runs and your remotes still connect while your speakers and streamers vanish.

Toggling the Local Network permission does not clear this, and neither does reinstalling Roon. That is not you doing something wrong. There is currently no way to reset this state on macOS at all, which Apple have acknowledged.

Step 1: find your network address

Open Terminal. You will find it in Applications > Utilities, or press Command and Space and type Terminal.

Paste this and press Return. It only reads, it changes nothing:

ifconfig | grep "inet " | grep -v 127.0.0.1

You will see one or more lines like this:

inet 192.168.1.42 netmask 0xffffff00 broadcast 192.168.1.255

Take the address after inet, replace the last number with 0, and add /24. So 192.168.1.42 becomes 192.168.1.0/24. If yours reads 10.0.0.37, it becomes 10.0.0.0/24.

If your line shows a netmask other than 0xffffff00, please post the output here instead and we will give you the right value. That is uncommon on a home network.

Step 2: apply it

Paste both blocks below into Terminal, one at a time, pressing Return after each. Replace 192.168.1.0/24 with your own value from step 1, and leave 224.0.0.0/4 exactly as it is. Terminal will ask for your Mac password. Nothing appears as you type it, which is normal.

sudo defaults write com.apple.network.local-network AllowedEthernetLocalNetworkAddresses -array "192.168.1.0/24" "224.0.0.0/4"
sudo defaults write com.apple.network.local-network AllowedWiFiLocalNetworkAddresses -array "192.168.1.0/24" "224.0.0.0/4"

Run both even if you only use Wi-Fi, or only Ethernet. They are separate settings and the unused one does no harm.

The 224.0.0.0/4 entry is not optional if you use Roon ARC. macOS treats multicast as local network traffic whatever else you exempt, and without it ARC cannot set up its connection.

Step 3: restart the Mac

Nothing changes until you do. After the restart, open Roon and go to Settings > Audio. Your devices should be listed again.

To check it applied

defaults read com.apple.network.local-network

No password needed, changes nothing. You should see both lists with your network and 224.0.0.0/4 in them.

What this trades, and how to undo it

This tells macOS to stop treating your network as a local network for every app on that Mac, not only Roon. It is the mechanism Apple provides for exactly this situation, but it is broader than Roon, and worth knowing before you run it.

To remove it later:

sudo defaults delete com.apple.network.local-network AllowedEthernetLocalNetworkAddresses
sudo defaults delete com.apple.network.local-network AllowedWiFiLocalNetworkAddresses

Then restart the Mac again.

This is a workaround, not a fix. R&D is working on the underlying cause. We do not have a timeframe.

5

Hey @mitchell_lim,

Wanted to follow up on this, since it’s still open on our side. Were you able to try the macOS 27 network permission workaround we outlined? We also have a KB guide on how to perform the workaround:

Fix Missing Audio Devices After a macOS Update in Roon

Please note, if we don’t hear back from you this thread may close automatically soon. If the thread auto-closes and you need further assistance, please submit a reopen support request via the technical support help form below and specify that the issue should be reopened. Thank you.

6

The above suggested workaround did solve my issue

7

Hello @mitchell_lim

Good to hear, and thank you for confirming.

One thing worth remembering for later: this is a workaround rather than a fix, and it applies to every app on that Mac, not only Roon. Once the underlying problem is resolved you can remove it with the two delete commands from the earlier post, followed by a restart.

We will close this thread now. If the devices start dropping out again, please start a new one and we will pick it up from there.