[Ticket in] B365/B1553 [FIX in B1583] Suddenly ARC can’t connect from cell network (or other foreign network)

[Suedkiez (Just a fellow user like you)]

I have a static IPv4 address. This always worked.

An online port check confirms that the port on the external IP is open:

(The static external IP of the router is the 109.xxx.xxx.xxx that’s being checked).

Roon check is OK:

Yet ARC gets no server connection when on the cell network or on another foreign network:

(ARC works fine when the phone is on the home wifi, that’s why the connection check says „last seen less than a minute ago“ in the screenshot).

Router is a Fritzbox 6690 Cable, FritzOS 8.03 (latest, no recent updates)

I’m using UPnP to the ROCK and the Fritzbox reports this as OK.

Rebooted router and ROCK. No change.

Haven’t used ARC in weeks, so I don’t know when this started, but the server connection check in ARC said „last seen 1 days ago“ when I noticed the problem earlier today while on cell network. (I don’t think I started ARC yesterday while on home wifi but can’t be 100% sure)

Any ideas?

[Alfred_van_Hoorn]

I had exactly the same issue! See also this post and this post.

Did you, like me, perhaps activate IPv6 in the EA branch a month ago by starting Roon Server and all Roon Remotes twice in succession? If I understand several posts on this forum correctly, this action added some rules to my Roon profile that caused problems (including possibly the ARC issue).

Last friday evening the issue with ARC was suddenly solved. I am still not sure why and I might be stubborn, but I think these rules were removed last Friday from my profile by the Roon team.That could have caused ARC to suddenly work again.

[Suedkiez (Just a fellow user like you)]

Thanks for comments

@Alfred_van_Hoorn

Did you, like me, perhaps activate IPv6 in the EA branch a month ago by starting Roon Server and all Roon Remotes twice in succession? If I understand several posts on this forum correctly, this action added some rules to my Roon profile that caused problems (including possibly the ARC issue).

Yes, but it worked after that, if I didn’t completely mess up my testing. The longer start time mentioned here cleared itself up later:

Discoverability test group

A little correction: My ARC app now seems to need a bit longer to launch, both on wifi and on cell. It takes about 4-5 seconds. The home screen is immediately visible but the app is temporarily unresponsive during this time, with the progress bar at the top not moving for a second or two. After this it seems to work normally. On the first try, it took longer, nearly 10 seconds or so, which was what made me start this post. But while writing I tried a few times more and it settled on the 4-5 s…

[Alfred_van_Hoorn]

@Suedkiez

Yes, but it worked after that, if I didn’t completely mess up my testing. The longer start time mentioned here cleared itself up later:

I my setup it worked also … but only for a few hours. After these hours ARC could not connect any longer to my Roon Server.

[Suedkiez (Just a fellow user like you)]

Hmm, weird. I don’t understand how the changes as detailed here would affect ARC communication to the Roon server on the external static IPv4 address. None of the “who is affected” details seem to apply to me

Plus there were 9 days between my first and second test in the other thread. I think I tested ARC the second time, too, but of course can’t be 100% sure anymore.

[Alfred_van_Hoorn]

I don’t understand either. But these kind of issues is probably one of the reasons that the Roon team has not yet activated IPv6.

[RiMac]

I had the same issue since last Wednesday. I was on IPV6. It worked for about a month and suddenly not anymore. After a restart of my titan it worked again and after a few hours it stopped again. I have disabled ipv6 on my modem and now it works ok again.

[DDPS]

I have a dual stack network and I can say that Roon had been very stable in spotty cell connection zones and then in the past week got crappy again, suddenly…meaning, once it loses cell connection and regains connection, I almost always have to quit and restart ARC, and that wasn’t necessary before the past week (since a few months back when this behavior had improved).

[Mr.Flibble]

AFAIK - this EA build had/has the IPv6 support enabled

@vova can you confirm

[Suedkiez (Just a fellow user like you)]

Yes, but they enabled it apparently since the announcement (but not sure, given the confusing communication, and not sure if it’s build specific) and it worked after that AFAICT

[Suedkiez (Just a fellow user like you)]

Restarting ARC hasn’t helped in my case.

Now I disabled IPv6 on the router and it doesn’t help. In fact it got slightly worse or at least different:

First, the connection check failed for „Cloud“ as well. Though I suppose this had nothing to do with me and my router:

Then ARC switched to this:

I suppose this means that the connection to the router failed hard, instead of hanging endlessly with the spinner rotating.

Given that I have a static external IPv4, it makes even less sense to me that disabling IPv6 on the router would have this effect.

Oh and the ARC test in the main app stuck at testing for a minute or two:

But then returned to OK:

No change in the ARC app after this, though

[Suedkiez (Just a fellow user like you)]

Huh, my Roon server stopped loading content from the Internet completely. I guess I will re-enable IPv6 on the router …

Edit: Done, and Roon server works again normally. Now I can’t test ARC because my phone is rebooting for iOS 26, stand by

[Suedkiez (Just a fellow user like you)]

Oh shoot me, now ARC works again, with the IPv6 settings just as they were before on the router.

Apologies everyone for bothering and thanks for the help! I guess I should have restarted my phone first to begin with. LOL. Another evening wasted.

[Alfred_van_Hoorn]

@Suedkiez

I guess I should have restarted my phone first to begin with

I really don’t know if you’re drawing the right conclusion. My Roon ARC also suddenly started working again and I did not restarted my iPhone.

[Suedkiez (Just a fellow user like you)]

Well, I made the mistake of not doing that first, so now we can’t know anymore

Nothing else changed on my side after I undid my changes, but maybe something was temporarily broken on the Roon side - the fact that ARC could not reach the Roon cloud for a while may be a hint that not all was well there.

[Arindal]

@Suedkiez

Any ideas?

Had exactly the same ARC connection issue, except for being fully on IPv6 on both ends and were unable to get satisfactory result of roon´s ARC connection test:

Deinstalled Roon EA and switched back to production build. Everything works flawlessly again including ARC.

[Suedkiez (Just a fellow user like you)]

Thanks, maybe another hint that there was hail in the Roon cloud

[Suedkiez (Just a fellow user like you)]

On the upside, Liquid Glass looks great on the phone

[DDPS]

Frankly, ARC got more stable for me again today. I do think there was a cloud issue…

[Suedkiez (Just a fellow user like you)]

Well it’s broken again, and this time a phone reboot doesn’t help.