Roon ARC connectivity issue with port 55002 despite troubleshooting (ref#5XSGI3)

What’s happening?

· Other

How can we help?

· None of the above

Other options

· Other

Describe the issue

Dear all,

Im having problems with Roon Arc and although I have tried everything in this article,

https://help.roonlabs.com/portal/en/kb/articles/arc-port-forwarding

and tried all the different configurations, also in the Router and they show the same port 55002, but unfortunately to no avail.
I have turned of VPN, turned off Apple Private Relay and briefly reduced the “security" on the router to see if that would help, but still not working…

Any help or suggestions would be highly appreciated :-)

Best regards,

Staale

Describe your network setup

Apple Mac Studio M2 Ultra, 192 GB w/macOS 15.3 Router: Swisscom Internet-Box 3 & Internet-Booster 5G
Speed: Download +/- 400 G/s & Upload +/- 100 G/s
Switch: Cisco PoE Switch CBS110-16PP-EU 16 Port
Roon: 2.0 (build 1496)

Can you post a copy of the diagnostic text that you see in the normal Roon client (not ARC) when you go to Settings → Roon ARC.

This may give more information to help get to the cause of your issue.

I believe that is what you can see in the 1/2 half of the screen-shot. If not, I’m not sure what you are referring to? Thank you for your willingness to help out.

{
“ipv4_connectivity”: {“status”:“NetworkError”,“status_code”:504,“error”:“error: Error: ETIMEDOUT, response code: undefined, body: undefined connected? undefined”},
“external_ip”: {“actual_external_ip”:“178.ddd.eee.fff”,“actual_external_ipv6”:“null”,“router_external_ip”:“92.aaa.bbb.ccc”},
“status”: “status”: MultipleNatFound
,
“natpmp_autoconfig”: {“status”:“NotFound”},
“upnp_autoconfig”: {“server_ip”:“192.168.1.1”,“found_upnp”:true}
}

Your screenshot did not appear properly.

However, the diagnostic text refers to ‘MultipleNatFound’. I have just posted a response to someone else with this issue at:

See if that posting helps.

Thank you. I indeed have 2 routers, but I did have that before as well. But I will have a look at your problem solving suggestions. Somehow I wonder if the Apple Private relay could be the culprit, but I have also tried with that turned off… Anyway, thank you very much and will report back on my “findings”.

My understanding is that this can cause issues with the reliability of ARC.

However, I believe the issues are not to do with the ability to make a connection. They certainly don’t result in the ‘Not Ready’ status on the Roon ARC settings page of the normal Roon Client. They are more to do with the Roon Server not recognizing the ARC device as the one previously connected resulting in the need to re-login and the consequent loss of all ARC downloaded content.

Edit: I have just realised that you may be referring to a setting on your Mac Roon Server. I don’t know - because I don’t use Macs - but it is quite possible that this setting on the Roon Server machine could cause issues with port forwarding.

Hi @staale.andresen ,

Can you please check to see if this setting might be interfering by any chance?

I would try to set it to Fixed or Off and see if that helps. Let us know!

Thanks, will do and revert back tomorrow.

Have a look at this link with regards to Apple Private Relay,

Hi Noris, I tried this (though I normally use LAN), but it did not work with WiFi either, nor with “Fixed” or “Off”. I mentioned earlier, that I have a suspicion, that the Apple “Privat Relay” may have something to do with it, although the Roon ARC does not work with the “Private Relay” on or off, but I have had some problems with other services, because of this.

Hi Noris, any thoughts or ideas?

Hi @staale.andresen,

Thank you for your post. Unfortunately, the blockage in this case is at the level of your provider, SwissCom, who has implemented carrier-grade network address translation (CG-NAT) across their accounts.

This means port forwarding is an impossibility without requesting a dedicated IPv4 address from SwissCom.

Fortunately, Tailscale offers a reliable workaround for Roon users in this situation. You can download the free Tailscale app to your Mac RoonServer machine and to your phone, and it will automatically traverse the CG-NAT layer imposed by SwissCom to allow for ARC to connect remotely.

Please see here for specific instructions and let us know if we can help further:

Hi Connor, thanks for the advice and suggestion. I will try it out and revert back to you (but possibly not before next week). Best Staale

Hi @staale.andresen,

If you’re finding Tailscale difficult to configure, you can also reach out directly to SwissCom to request a dedicated IP address. I recommend informing them that you’re attempting to use port forwarding but are blocked by CG-NAT; they’ll likely be familiar with the situation.

Hi Connor, seems to work now, with Tailscale :+1:
Thanks a lot to everyone, Staale

Wonderful to hear, @staale.andresen! Please reach out in a new topic thread if anything comes up and we’ll be here to support.