I don’t think Roon uses IP multicast for actual streaming, only for device discovery, but I’ll let Roon people answer that if they want to. OTOH, I agree that UniFi (or its more consumer-friendly AmpliFi younger sibling) solve lots of problems relative to other consumer-grade networking gear.
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I AM an IT expert and the one thing I didn’t see asked or answered here was what brand and model is your networking equipment? Does it have the latest firmware? How old is is your networking equipment? Are you using the box provided by your ISP?
We asked multiple times.
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Hi @DanMtsn,
Did you ever get a chance to open your iPad app? I still am not seeing any log reports being delivered on our end.
Also, as we mentioned a few times in the thread, knowing your exact network setup details might allow us to give you some better suggestions on how you can modify the network to work better for multicast traffic.
You’re correct: Roon can’t possibly use IP multicast for streaming once they moved RAAT to TCP a few years back (for those who don’t know, IP multicast supports only UDP, because the semantics of reliable delivery are unclear when there’s more than 1 destination). I have fond memories of watching live video from the Space Shuttle on the MBone in grad school, but, alas, IP multicast has arguably regressed, rather than progressed, in the last 20 years. It seems that many attempts at using multicast in anything other than a flat network topology end up with problems: Roon is not the only application I’ve seen fall into this trap.
However, to have a configurationless system, fundamentally, you do need a well-known to say, “Hello, is anybody out there” 
on. You could use IP broadcast, but that’s kludgy and inefficient.
Sigh. One of my favorite, but nearly orphaned, technologies…
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I’ve 25 years in IT / Networking / Security and I had a similar issue with Roon disconnecting on Wi-Fi. everything else worked great (including MMORPGs and streaming) and I was convinced it was Roon. It lasted over a year until I replaced my access point for an unrelated problem. My router was garbage and couldn’t handle the traffic volume / number of concurrent sessions.
Just saying.
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However, the problem being discussed here by many doesn’t (certainly doesn’t in my case) relate to issues with the ISP or ISP provided router.
Roon ‘Device Discovery’ works flawlessly in my system over wi-fi (and IOS or Windows 10 laptop) when I have a basic consumer network switch (TP-Link) connected to my network, and my Roon NUC is connected to the switch.
However, Roon ‘Device Discovery’ simply does not work at all with either of 2 managed switches (set to default configuration) replacing the TP-Link when I have a very specific AV item (a Sky Q Satellite TV box) attached to the switch.
A very different scenario.
I have been told by Roon that the problem lies with my Cisco 2960 managed switch, and that managed switches (even those configured with basic defaults) should simply be avoided.
Fernando_Pereira has informed me in this thread that:
“Roon uses IP multicast for device discovery. Most other apps don’t AFAIK. Some routers and managed switches don’t handle IP multicast right (or need specific configuration to do so)”.
Now, this may well be the case. I am perfectly willing to believe that the issue is related to IP multicast and managed switches. However, it does beg the question:
Why does Roon use IP multicast for device discovery (but I understand not for the streaming process itself) when it is presumably known by Roon that some routers and managed switches “don’t handle IP multicast right (or need specific configuration to do so)”? What are the advantages of using IP multicast for device discovery that have resulted in this decision, and why does a completely unrelated device being attached to the switch result in the Roon device discovery process being broken?
I purchased a managed switch (Cisco 2960 - in fact I have two of them) because as a ‘professional’ device, it is more robust and supports more ports than basic consumer switches. I did not purchase them because I wanted to actively manage network traffic through the switch. I am sure that many others have done exactly the same but don’t currently use a Sky Q box and so have not (yet) experienced the issue.
The above post perhaps comes across as though I am not satisfied by Roon and the overall Roon experience. I would like to make it clear that this could not be further from the case.
Roon has hugely enhanced my music listening experience in very many ways since I started using it some 18 months ago. Most of the small number of problems I have experienced have been minor, and all but the one now being discussed have been resolved relatively quickly. I love the look and feel of the product as well as the multi-room capability and the many other features of Roon.
I have not come across any other product that comes close, and although I subscribe on an annual basis, I very much expect to be a lifetime subscriber.
The issue about which I have posted above is a minor one (to me), because there are work arounds. However, I am simply curious to understand better why the problem occurs, or has been allowed to occur - not simply that “managed switches are to be avoided because they may not handle IP multicast right”.
I think the statement should more along the lines of "Managed switches can pose problems for roon as:-
- Some need configuring to work with Roon as by default they don’t handle IP multicast right.
- Some switches don’t work properly at all
- We can’t test all managed switches to tell you which is which or the configuration options so unless you are an expert use an unmanaged switch."
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I have no general problem with your summary, but:
Why did Roon decide to use IP Multicast for device discovery if it is ‘known’ that there will be issues with some (and possibly many) managed switches that Roon users will use? Are there no alternatives to IP multicast for device discovery?
and
Cisco is a well known and respected brand of switch used by very many (probably most in my experience) professional IT network installations, and the 2960 is a widely used example of their managed switches. Why would the Cisco 2960 switch “not handle IP multicast right”? They have had plenty of time and experience to make sure that they handle IP multicast ‘right’ by default.
I can’t answer definitely the choice but it might come from the Sooloos background which was a much smaller closed system. Just a guess.
You’d have to ask Cisco about the switch.
Though just because something comes from a big name manufacturer doesn’t mean it’s perfect. That’s one of the reasons for new models etc 
Having had to go round 1500 PCs to replace their Network cards because of a design fault back in the day I can testify to that.
Unmanaged switch knowledge needed about multicast - plug it in.
2960 - here’s the multicast section of the manual
This chapter describes how to configure Internet Group Management Protocol (IGMP) snooping on the Catalyst 2960 and 2960-S switches, including an application of local IGMP snooping, Multicast VLAN Registration (MVR). It also includes procedures for controlling multicast group membership by using IGMP filtering and procedures for configuring the IGMP throttling action. Unless otherwise noted, the term switch refers to a standalone switch and a switch stack.
Okay - as I said, this isn’t really such a big deal for me and only affects one of my systems. My main system uses the Roon app on an ethernet connected PC which doesn’t experience the issue.
I may at some stage in the future (when I have the time and inclination) invest in a console cable, download the Cisco 2960 manual (thanks for the link) and play around with the ‘IGMP Snooping’ configuration of my switch. Until then, I’ll continue to use my current workaround.
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@noris Sorry, I wasn’t able to even play any music yesterday. Here’s what you asked for:
the iPad app is running right now, I’m not sure if this is what you need. By the way it works without dropouts…
Regarding my network, there’s a Compal ch7465lg-lc router, provided by my ISP. There’s no other networking device in use (switch, or hub or repeater, nothing). Roon runs on a Win10 computer with an i5 processor and 16gb RAM. This PC is wired to the router. All other Roon endpoints are wireless. I have the following Roon endpoints on wifi:
- two Raspberry Pi4 with HifiBerry hats
- two Chromecasts
- one iPhone and one iPad are occasionally used as endpoints for heaphone listening, but their main use is as remotes.
The most used wifi endpoint is forced to connect to 5ghz.
There are 15 wifi devices on the network. We’re not in a crowded area, there are about 4-5 houses around us and the closest one is about 10-15 meters away from us.
Please let me know if you need more details about the network.
Not a lot of information about that device but if you look at the WiFi performance in the link below there are a lot of red and yellow bars
https://nl.hardware.info/routers.9/compal-ch7465lg-zg-ziggo-connect-box.371250
Whereas something better
https://nl.hardware.info/routers.9/asus-rt-ax58u.555855
This looks remarkably like the latest Virgin Media hub. Which is a piece of trash!
The first thing I did when I was supplied with it was to switch it to modem-mode only, and attach a decent ASUS router to it.
Everything runs perfectly now.
People have to realise that they need to invest in some decent network hardware to ensure the network works. It’s not expensive. Just takes a bit of effort, that’s all.
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thank you @ged_hickman1
I’m sure there are plenty of better routers than mine 
I’m waiting for the full diagnosis from @noris
This is a key point. Setting to default is meaningless unless you know exactly what “default” actually is. As I mentioned before, and as @ged_hickman1 posted from the setup guide of these switches, they are NOT plug and play.
In many ways I would love to see you/someone read and understand that guide and post exactly what config should be used to get multicast etc working.
I understand that, although it will obviously require a bit of effort, the purchase of a console cable and the installation of ‘Putty’ in order for me to give it a go. I may get round to it in time.
However, the quote of mine that you have just posted above is not quite complete.
I stated that “Roon Device Discovery simply does not work at all with either of 2 managed switches I own”, but with a qualification that you missed out in your reply. That qualification is that Ron’s device discovery works flawlessly using the Cisco switches up until I connect a completely independant device (Sky Q Satellite TV box) to the switch .At this point, the Sky Q Satellite TV box (and all other devices connected to the switch) continue to work, but Roon’s device discovery process immediately fails over wi-fi.
Intuitively, it would appear that there are 3 possible explanations for the issue:
-
Roon’s implementation of IP multicast device discovery is problematical in that it fails to discover the Roon Rock NUC over wi-fi when the Sky Q satellite TV box is connected to the switch, although it continues to find the Roon Rock NUC when using an ethernet connected Roon app (Windows 10 desktop).
-
Cisco’s implementation of IP multicast is problematical or not configured properly because Roon’s implementation of IP multicast device discovery fails to work over wi-fi as soon as the completely independent Sky Q satellite box is connected to the Cisco switch. However, it does continue to work using an ethernet connected Roon app (Windows 10 desktop).
-
The problem lies with the Sky Q Satellite TV box, because Roon’s IP multicast device discovery works perfectly in conjunction with the Cisco switch until such time as the Sky Q TV box is connected to the Cisco switch. At this point in time, device discovery continues to work from an ethernet connected Roon app (WIndows 10 desktop), but not from a Roon app using wi-fi. What might the Sky Q TV box be doing to disrupt Roon’s IP multicast device discovery.
I am still not entirely convinced that any of the above explanations is more likely to be valid than either of the others.
maybe it would be better if the SkyQ/Cisco conversation is split into a new thread since it refers to a very specific device/context?
It looks like you have a WiFi problem. Both iPad and iPhone connecting to you Roon core over WiFi.