iRadio and n-Stream: strange behaviour

Certainly sound strange, but mains carried Ethernet are usually big no no's with hifi and streaming

1) PLA / Ethernet over mains creates a phenomenal amount of RF pollution which will smear detail in audio circuits.

2) PLA / Ethernet over mains is a single  collision domain, ie only one device can transmit at a time, so there are either token or collision  avoidance mechanisms  required ( like the early ethernet technologies of 20 years ago ) which means when multiple hosts try and share that link, the performance will rapidly fall off. Simple web browser use or peer to peer communications are fine, if you live with the RFI pollution, but they are not really suitable for much else.

I would try wired Ethernet through a switch and then you know your LAN is optimal for audio use.

Simon

Simon

Most grateful for your response. I know that there are reservations about Ethernet over mains, but I have the problem that my router is on a different floor of the house from the hifi, and there is no sensible way of running wiring between them. What I will try shortly is a SQ comparison between wired over mains and wireless, though I know the latter brings its own set of issues. I do want to be able to stream 96 and 192/24, so I don't really see an alternative at the moment to what I'm doing.

To get back to my stated problem, it only seems to apply to iRadio, not uPnP, so further ideas (from Simon or anyone else!) would be most welcome.

Thaks again, Simon.

Paul

I used to run ethernet over mains, but find wireless actually more reliable since I bought an airport extreme. I too have my hifi on a different floor to my router/NAS, I don't really fancy running cables between them.

Steven

Are you running higher resolution rates successfully this way?

Paul

Well what have you  got going over the Ethernet over mains( PLA) ?  These really are not suitable for more involved LAN usage in my opinion. I don't know where you are with your upnp server in this setup? Is this going  over the PLA link?  If it working for upnp and not web radio you simply need to look at the differences. Where does your wireless access point connect to?  Is that the wireless access point on the router? In which case you must confirm your PLA supports multicast? Otherwise nStream will lose sync with your network player as your PLA is filtering the important discovery multicast from your Nstream.

The multicast travels 

Nstream-> wireless -> wifi AP -> switch -> Ethernet segment -> network player. 

Each of those links must support multicast.

Because multicast uses UDP, it is essentialI your components correctly retransmitt the UDP discovery frame after a collision. Does your PLA do this?

In my expierience the problems you describe occur when a network bridge ( such as PLA) or wifi don't multicast correctly. I am intriqued how your upnp works though? can you do a character diagram of your setup?

Simon

Hi Simon

Thanks for your continued interest. Not quite sure how to do this as a diagram, but I'll try and do it with words, and hopefully you'll get the sense. I have 30Mbit/s Virginmedia broadband coming in, attached to one of their Superhubs (made by Netgear) which I am using in 'cable modem only' mode. ie I'm not using its routing capability which is switched off. This is attached to a Belkin N750 router, which I'm using because it (allegedly) has superior wifi capabilities, and certainly does have a couple of USBs which I'm using to network two printers. Attached by Ethernet to the Belkin are (a) my desktop PC, (b) my Synology NAS, which is (amongst other things) providing UPnP which the SuperUniti seems to pick up just fine, and (c) the mains Ethernet thingy which is a Solwise Gigabit system (this only has one use, at the moment, which is providing network connection to the Superuniti). Wirelessly, my iPad and iPhone connect via the Belkin when I'm at home.

One thing I didn't mention in my OP, because I'm not sure about it yet, is that I briefly had these connections working through the VM Superhub with its routing capability switched on, rather than the Belkin. My impression was that I wasn't getting drop-outs when I had it set up like this, but frankly I could just have had nStream working continuously at this point and I would need to test this again. I wanted to see whether anyone else had had similar experiences rather than complicate my OP too much. But if I'm right about that, it opens up the possibility that the Belkin router (which seems blameless in all other respects) might be responsible for the drop-outs. In which case maybe there is a setting I can play with - can you point me in an appropriate direction?

Help much appreciated, Simon.

Paul

Paul, I assume you have have only one DHCP instance switched on?  I am intriqued by you say you had got working. Why don't you repeat that, and remove the netgear... In any case it appears you are still using the cable modem as the router, and the netgear only as a switch and wifi access point. Anyway if it all works with the Netgear taken out then that points to multicast failing on the Netgear wifi, or poor timing for your DHCP server.

Simon

I can't completely remove the Netgear, as it performs two functions, cable modem and router. I can switch it off as a router, which I've done, as I'm using the Belkin for this role. But I have to use the cable modem element. It's designed to allow this virtual internal split to happen.

Cheers

Paul

Ok, so try again removing the Belkin N750. (i meant saying that rather than Netgear) Something on your setup is blocking multicast

Quickly doing a search on the web, I see indeed that the Belkin N750 is notorious for  or has faulty multicast support.

http://www.fixya.com/search/p2...and_n_rout/multicast

A lot of cheap consumernetwork stuff is really not fit for purpose and causes so much fustration.

My advice:

• Keep it simple
• Use quality brands like Linksys, Netgear where you can.
• Use wired Ethernet where possible (but that might not be an issue here, but on hires with PLA you may get a stuttering if someone turns ohaulier dryer or fridge compressor switcheon off as well as audiodetail masking RFI)
• Ensure your wireless access point  explicitly supports multicast

Well, Simon, to (I think) finish the story, I tried Belkin's online support, got two pretty unhelpful responses, and have given up on the Belkin unit. I'm now running the Virgin Superhub (made by Netgear) as a full modem/router, and have had no further drop-outs (yet, it's early days). I think it's going to work. I've lost the ability to plug my printers into the Belkin's USBs and thus network them, but that's less important to me than having iRadio working reliably.

One issue I did have when I switched over to the Superhub was that for some reason the nStream app on my iPad and iPhone wouldn't find my SU. However, I searched on these forums and discovered others have had the same problem with the same kit, and it's fixed by entering the SU IP address (which had changed of course with the router switch) manually. Then everything works fine, though I'm not sure why it should be necessary.

Many thanks for your help and advice, Simon.

Paul

Glad you got it sorted...

I recommend removing anything from the chain with 'belkin' in the name.

Thanks! One oddity remains. I mentioned that I had to input the new IP address of the SU manually on the Netgear. NStream is working fine, but it's still not seeing the Naim pretty logo and identifying the SU for itself. Somehow, the Netgear router is blocking this info between the SU and nStream. It doesn't matter much, but can anyone explain, and maybe cure?

Special thanks to Simon for his help!

Paul

Paul, I hate to say it, but it stillsounds like broadcast or multicast is being filtered to some extent. Have you checked 

A) netgear has multicast filtering off or multicast enabled

B) perhaps Ethernet over mains is filtering the multicast or broadcast?

Can you run a long lead of Cat5 UTP cable to bypass the Ethernet over mains  just to see if it gets rid of the problem. Without network sniffers like wireshark it is a process of elimination

Simon

Simon

I really can't run a cable, not without buying half a mile of the stuff (I exaggerate slightly). But since everything including nStream is working well (and the SQ is really pretty good) I'm disinclined to spend ages sorting out something that doesn't matter much. But I will look at the Virgin/Netgear settings to see if I can find anything to play with.

Cheers

Paul

PS Multicast is shown as 'enabled' in my Netgear settings. And the Ethernet-over-mains thing you hate so much is certainly not responsible for this minor problem as it was working fine over the (now returned) Belkin.

The super hub is not a good device i assume you have read virgins forum about it?

Also ethernet cable is so cheap, ebay has 15 metres terminated for 1.89 delivered. Buy one. Run it to the su temporaily and see if the problem goes away.

Paul,  sorry I am confused, I thought the setup was NOT working with the Belkin?

Anyway, in short the upnp server, Nstream, and network player must have a simple reliable compliant Ethernet / TCP/IP connectivity between them, and then there are no issues. Anything that does not support aspects of TCP/IP muticast, broadcast, UDP across the subnet will trip up the system, and really should not be used in home LAN equipment.

As Gary says running a temporary lead might determine where the Ethernet over mains is responsible or not. The reason I dislike them, is often they are very poorly designed with troublesome performance and bad side effects.

If however you can live with the current issues, then fine. But quite honestly, from a network point of view this is kindergarten stuff, and if equipment is struggling here, you don't know what horrors await around the corner.

For info: poor broadcast or delayed broadcast frame implementation can affect reliable DHCP operation.  Poor multicast operation affects Apple streaming and upnp synchronisation disc device discovery.

Wireless access points on some routers are notorious in the above area, and for multimedia I recommend a cheap and humble Airport express, connected off your switch with its own Wireless network (SSID), and use that for your Apple or upnp control points.

Simon

Simon

The problem with the Belkin was that it would lose the connection between iRadio and the SU, quite a lot. But while it was working, it worked, and it had no problem identifying the SU to nStream. I've now returned the Belkin whence it came, and am hopeful of getting a full refund. The Virgin/Netgear has no problem with transmitting iRadio or UPnP to the SU without losing signal at all, but mysteriously the SU with its logo doesn't show up in nStream. I got round this by entering the IP address manually, and nStream works fine - though it still hasn't formally identified the SU. As I said earlier, this really doesn't matter.

Regards

Paul

Excellent, enjoy your music

Really grateful for your help.

Paul