Roon ARC unable to access core with latest version of macOS

I am unable to get Roon ARC functioning on my Mac. Here is the diagnostics data…{
“connectivity”: {“status”:“NetworkError”,“status_code”:504,“error”:“error: Error: ETIMEDOUT, response code: undefined, body: undefined connected? undefined”},
“external_ip”: {“actual_external_ip”:“”,“router_external_ip”:“”},
“natpmp_autoconfig”: {“server_ip”:“”,“found_natpmp”:true},
“upnp_autoconfig”: {“server_ip”:“”,“found_upnp”:true}

Any ideas for a remedy? I have enabled UPNP on my router.

Similar problem. Imac will connect to iphone on the same network using wifi.

Once I turn off the wifi I get an error message:

“uh oh, something’s not right - Make sure your Roon Core is turned on and that you’re connected to the same network.”

iphone data is on

EDIT: Now working on the iphone…

Here is a screenshot from my Mac…

I failed to first download Roon Arc, my comments were from the Roon app.

My diagnostics screen is similar…

EDIT: Now working on the iphone…

You have to be able to connect to your Core from the internet on port 55002.
This means your router must be connected to the internet without NAT and have a forward on port 55002 to your Core.
With upnp this allegedly works automatically, but i have no router to support this so did this manually.
When i had the forward configured it worked instantly, the error message simular to yours disappeared.

Be aware tha some providers do not give you a valid ip adress and use a client network with NAT.
This can be a problem that your provider must fix for you.

External IP port 55002 → firewall (forwards port 55002) → with ARC port 55002


works fine on mac mini m1

You could also have a valid ipv6 address but not a valid ipv4 address.

True, but that is not a very common, so did not explore that path.
I saw postings that stated the use of a VPN connection and using Arc over that connection, thus not exposing the port on the external/WAN IP.

Here is a screenshot of my router settings…

Do I have the right idea? Still is not working.

From the picture it looks like you are forwarding or allowing port 55002 on to access port 55002 on 192.168,0.34.

Both IP addresses are non routables over the internet and only usable in private networks.
This is not likely to work, as far as i can tell from the information provided.

My WAN ip is and i am allowing port 54321 to be forwarded to my core on port 54321.
The WAN ip is accessible from the internet and can be reached.
192.168.20.x is an internal network that “the internet” has no knowledge about.

1 Like

Here are the IPV4 segments designated for internal networks: - (10/8 prefix) - (172.16/12 prefix) - (192.168/16 prefix)

Source: RFC 1918: Address Allocation for Private Internets
Page 4.

Your local IPV4 network usually starts with one of these. This is normal. If your router has an IP address in this range, that is a problem. As I mentioned above, some ISPs don’t provide a real IPv4 address, but DO provide an IPv6 address. My cellular telephone provider is one such company. This makes sense for a cell phone as cellular data tends to not be a great solution for running any sort of server, which Roon is doing here.

If you don’t have a routable IPv6 address, a VPN could be a possible solution if your provider allows multiple devices on the same account to reside on the same subnet.

You don’t put an IP address in the “internal ports” field. That should be “55002”.

Also, you need to set this rule for Roon Core at IP Address, not "John’s iMac at

I do have some concerns about the fact that your iMac and Roon Core might be on different subnets. Of the subnet mask is, then they are on different subnets. But ignore this for now…change the “internal ports” entry to “55002” and the host to your Roon Core and see what happens.

I don’t have so much knowledge about networks, but minutes ago I could configure the network to Connect the Roon Arc app, in my case I use an internal Wifi 6 router for the ROCK and the other devices, but the internet come from the ISP router, so was necessary to open the port in the ISP router too.