Sound quality - Roon RAAT vs Roon Air

[mdconnelly]

When I was having the same problem, I bought a cheap 100mbps switch from Amazon, plugged the ethernet cat6 from router into it and then output to the Devialet. It fully stopped the stuttering and errors I was getting at the time. And it worked perfectly for all music. As @David A said, it didn’t fix the problem but it was a slick and cheap workaround that had no impact on sound quality - at least to these ears.

After Devialet released the update about a year ago, they claimed it further improved the issue but did not eliminate the stuttered with hi-res music at gigabit speed - at least not for me and numerous others. But then, a few months later and for an unrelated reason, I bought a NUC, installed ROCk, hooked it all up *at gigabit speed* and damn, it worked perfectly. No stuttering or drop outs at all. My prior RoonServer was a fairly powerful i7 Win 10 desktop PC so I didn’t suspect any issues with it. But, for whatever reason, using ROCK on a NUC fully eliminated the problem for me and I now no longer use the 100mbps switch. I did ask Devialet how/why/what that might be but never got an answer.

[Delija]

@David A
I don't use any resample for PCM either, but I do have some number of 192/24 releases and I also use Qobuz which has a lot of hi-res releases.

[Pim]

When I was having the same problem, I bought a cheap 100mbps switch from Amazon, plugged the ethernet cat6 from router into it and then output to the Devialet.  It fully stopped the stuttering and errors I was getting at the time.  And it worked perfectly for all music.  As @David A said, it didn’t fix the problem but it was a slick and cheap workaround that had no impact on sound quality - at least to these ears.

After Devialet released the update about a year ago, they claimed it further improved the issue but did not eliminate the stuttered with hi-res music at gigabit speed - at least not for me and numerous others.  But then, a few months later and for an unrelated reason, I bought a NUC, installed ROCk, hooked it all up *at gigabit speed* and damn, it worked perfectly.  No stuttering or drop outs at all.  My prior RoonServer was a fairly powerful i7 Win 10 desktop PC so I didn’t suspect any issues with it.  But, for whatever reason, using ROCK on a NUC fully eliminated the problem for me and I now no longer use the 100mbps switch.  I did ask Devialet how/why/what that might be but never got an answer.

I went from a Mac Mini to running a NUC with ROCK. At first I had a problem with the NUC freezing up which turned out to be a faulty SSD. Once that was replaced it worked perfectly for 11 days until I went to work away from home. My wife complained about it just stopping to play toward the end of my 7 weeks away from home. I was home for a few days and RAAT stopped playing a few times a day. I ended up just using AIR.

So one man's solution is another's problem. I'm about to move the Od'A to another room where it will have to work on WIFI and I will bring my D200, which only has AIR, back to the living room so I suppose the problem will be a temporary one.

I wonder if the stoppage can be prevented by regularly re-starting the NUC. I've already set up the BIOS to start up automatically after a power failure so I could just put it on a clock switch that turns off for 1 minute every week in the middle of the night. 100Mb switch or clock switch, either way are dirt cheap solutions.

[Jnan_devi]

RAAT Vs AIR = Both sound same for me. I prefer RAAT, without any further reasons. However I keep switching between both once in a while. Maybe in future i might prefer one Vs other.
Regarding network, ROCK on NUC is near router area (Wired) and decent net speeds (~500MHz); Router and Satellites, Netgear Orbi753 does great job. CAT8 pulled upto Devialet from Router. Devialet is wired with gigabit wire and switch.

No drops observed since last Tuesday (Bought pre-owned 220Pro this week Tuesday). Loving everything about it ever since i sold/moved out of Devialet (Le 120 in 2017). Back to Devialet and my system sounds superb all over again.

[mdconnelly]

When I was having the same problem, I bought a cheap 100mbps switch from Amazon, plugged the ethernet cat6 from router into it and then output to the Devialet.  It fully stopped the stuttering and errors I was getting at the time.  And it worked perfectly for all music.  As @David A said, it didn’t fix the problem but it was a slick and cheap workaround that had no impact on sound quality - at least to these ears.

After Devialet released the update about a year ago, they claimed it further improved the issue but did not eliminate the stuttered with hi-res music at gigabit speed - at least not for me and numerous others.  But then, a few months later and for an unrelated reason, I bought a NUC, installed ROCk, hooked it all up *at gigabit speed* and damn, it worked perfectly.  No stuttering or drop outs at all.  My prior RoonServer was a fairly powerful i7 Win 10 desktop PC so I didn’t suspect any issues with it.  But, for whatever reason, using ROCK on a NUC fully eliminated the problem for me and I now no longer use the 100mbps switch.  I did ask Devialet how/why/what that might be but never got an answer.

I went from a Mac Mini to running a NUC with ROCK. At first I had a problem with the NUC freezing up which turned out to be a faulty SSD. Once that was replaced it worked perfectly for 11 days until I went to work away from home. My wife complained about it just stopping to play toward the end of my 7 weeks away from home. I was home for a few days and RAAT stopped playing a few times a day. I ended up just using AIR.

So one man's solution is another's problem. I'm about to move the Od'A to another room where it will have to work on WIFI and I will bring my D200, which only has AIR, back to the living room so I suppose the problem will be a temporary one.

I wonder if the stoppage can be prevented by regularly re-starting the NUC. I've already set up the BIOS to start up automatically after a power failure so I could just put it on a clock switch that turns off for 1 minute every week in the middle of the night. 100Mb switch or clock switch, either way are dirt cheap solutions.

Pim,  interesting... my NUC has not rebooted once in about 8 months now (I also have it on a UPS to avoid reboots resulting from power flickers).   Roon only restarts when they release an update.   It would be interesting to see what, if anything, shows up in the Roon logs when it stops.  Does it occur with your music residing on a hard drive or via streaming from Qobuz or Tidal?   If locally, perhaps a hard-drive issue.  If streaming, perhaps a flakey internet connection?  I have had music stop when streaming to a wifi connected endpoint, but I blame that on wifi congestion.   No issues at all to my hard-wired Expert Pro.  Can't imagine it being a ROCK on NUC issue but who knows.

[Saint0]

Nice to know the ETGERRegen fixed the problem; however it's pretty pricy at $650 (USD). I wonder if a cheap 100M switch per Devialet and Roon's recommendation will do the same?

I think you're looking at my post in the wrong way.

First, the ETHERRegen hasn't fixed the problem. The problem is a problem with Devialet's handling of ethernet input. The problem still exists today. The last firmware update, now nearly a year old now, improved things somewhat but still didn't fix the whole of the problem. Some people are still reporting the issue after that last update.

Using a switch to connect to the Devialet at 100 mbps doesn't fix the problem, it's an effective work around that manages to avoid the problem, just as using wifi with RAAT instead of ethernet also avoids the problem. Work arounds are great but they don't fix the problem, they just let you avoid triggering the problem and that's a great thing to do if there isn't a fix for the problem. 

If you want to use an ethernet connection, you just want an ethernet related workaround for this problem and you aren't interested in chasing an improvement in sound quality by going down the rabbit hole of audiophile switches, then definitely by a standard100 mbps switch. It should let you avoid the problem entirely, just as the ETHERRegen does, but normal 100 mbps switches and audiophile 100 mbps switches like the ETHERRegen don't solve the problem, they just avoid the problem. Solving the problem requires a firmware fix from Devialet and they don't seem to be in a hurry to fix the bug they introduced or even to roll out the last couple of features they originally promised for the CI board which were still listed as outstanding in the info sheet with the last firmware update a year of so ago. The problem lies in Devialet's handling of the incoming ethernet stream. Using a lower speed ethernet stream doesn't fix the problem, it just avoids triggering the problem which gives us a result we want but it's definitely not the ideal solution.

I didn't buy the ETHERRegen to avoid this problem. I was getting by quite fine prior to getting the ETHERRegen simply by not streaming any 24/192 resolution music to my Devialet because I didn't get the problem at lower resolutions but others were not so fortunate. If I had wanted to swap to a 100mbps switch in order to avoid this problem occurring then I would have bought a normal and much cheaper 100 mbps switch and I would have done so much earlier than I bought the ETHERRegen. Getting the workaround of a 100 mbps connection to the Devialet from the ETHERRegen was a free bonus for me, nice to have but not essential since I wasn't running into the problem as long as I avoided 24/192 streams.

Interesting development, Roon dropped the new 1.8 (Build 831) last week. I've been using AIR. After reading the previous posts I decided to try Roon Ready again after the update. I'm not sure what was changed, but the latest Roon version fixed the audio dropout issue. I've been playing Tidal Master MQA at max sample rate last few days, and no problems so far. I've not made any changes to the network or setup, still using the same old GigE switch.

Just to recap, yes, Devialet had major Ethernet issues with Roon Ready before. It was a catastrophic failure and unusable, but the latest update fixed the problem (for my system at least).

The random audio dropout started after the Roon 1.8 update. The short, random audio dropout is different from the previous Ethernet connectivity failures. I contacted Roon. They denied it's caused by 1.8 changes, and claimed it's a Devialet Ethernet stack issue. They explained that Roon Ready decode the file to raw PCM, and Devialet's processor can't handle the bit rate of HiRes MQA files. They recommended the 100Mb/s switch workaround. I contacted Devialet as well, and they don't know what's the root cause, and also suggested to try downgrading the switch to 100Mb/s per Roon's recommendation. I decided to use Devialet AIR instead, and it works perfectly over Ethernet.

I have a few issues with Roon's explanations:
1. The Roon Ready dropout is not related to bit rate, it occurred with low bit rate internet Radio streaming as well as local & Tidal CD or HiRes files.
2. Changing to 100Mb/s switch won't change the raw PCM bit rate.
3. If it's a generic Devialet Ethernet issue, it should affect AIR as well. AIR and ROON Ready just different protocol over Ethernet, but AIR works perfectly over Ethernet.
4. Finally the dropout issue follows the Roon software version, it started with the 1.8 update and fixed after the latest 1.8 version.

I don't claim to know exactly what's going on behind the curtain. Based on my observation with my system, the audio dropout seems to be a Roon issue as it follows the Roon 1.8 changes.

[David A]

…
I have a few issues with Roon's explanations:
1. The Roon Ready dropout is not related to bit rate, it occurred with low bit rate internet Radio streaming as well as local & Tidal CD or HiRes files.
2. Changing to 100Mb/s switch won't change the raw PCM bit rate.
3. If it's a generic Devialet Ethernet issue, it should affect AIR as well. AIR and ROON Ready just different protocol over Ethernet, but AIR works perfectly over Ethernet.
…

You're right, AIR and RAAT are different protocols and neither changes the PCM bit rate.

That doesn't mean they're the same. The PCM signal isn't what's streamed from Roon over ethernet. What's streamed is sequential fragments of the PSM signal bundled into packages with other things like extra code so the receiving device has the info required to reassemble the PCM stream in the right order, and code for an error correction system. In addition the receiving device, in our case our Devialet's, sends data back to Roon. That includes info required to tell Roon when to stream more data (the data is not streamed in real time as the music plays, it's streamed in bursts, the PCM stream is reassembled and fed into a buffer from where it's fed to the DAC at the correct speed for playback) and with RAAT the Devialet also sends back info about volume, tone control, and other settings like SAM which gets displayed by Roon in its signal path window but which aren't displayed for AIR because Devialet never built provision for that kind of info display into the AIR protocol.

One result of all of this is that RAAT uses more bandwidth to stream the same audio signal as AIR does. Back when the gigabit ethernet connection issue was under regular discussion here, someone posted test results showing how much bandwidth was used to stream the same audio signal via AIR and via RAAT. If I remember correctly the figures were something under 10 mbps for AIR and something a bit over 11 mbps for RAAT. Both streams utilise only a small percentage of the bandwidth available over a 100 mbps connection and a minuscule percentage of the bandwidth available over a 1000 mbps connection and neither should be a problem with either connection speed but the RAAT stream does present problems for the Devialet over a 1000 mbps connection while the AIR stream does not.
.
It's a mistake to think of an ethernet stream as a simple stream of PCM audio like the stream sent over coaxial or optical digital connections. What is being streamed isn't an audio signal, it's a data signal which is contained in data packets which contain fragments of the PCM audio data plus other data required for data handling. AIR and RAAT are different protocols and they use different packaging arrangements. There's more non-PCM audio signal data contained in RAAT packets than in AIR packets because of the error correction code and other things which RAAT provides but AIR does not and that means that the RAAT data stream needs to be handled differently to the AIR data stream. Devialet hasn't yet got its handling of RAAT correct and it seems that what it has not yet got correct with RAAT isn't an issue for what needs to be done to handle an AIR data stream.

While the problem lies with Devialet's ethernet handling, it involves Devialet's handling of one data protocol, RAAT, but not a different protocol, AIR. Essentially it seems to be a protocol handling problem related to ethernet connections rather than an ethernet handling problem which affects all data sent via ethernet. Those 2 problems may sound similar but they aren't the same problem.

[thumb5]

I don't want to start an argument, and am not an apologist for Devialet, but the fact that there are problems with RAAT but not AIR over Gigabit Ethernet to a Devialet can equally be seen as evidence of a problem in the implementation of RAAT, albeit one which is triggered by some aspect of Devialet's Ethernet interface (software and/or hardware).  It is the combination of RAAT, Devialet and a GbE physical link which results in incorrect behaviour, and isolating any single part of that combination as "the problem" is perhaps premature.  Just for the sake of neutrality and balance...

[mdconnelly]

I don't want to start an argument, and am not an apologist for Devialet, but the fact that there are problems with RAAT but not AIR over Gigabit Ethernet to a Devialet can equally be seen as evidence of a problem in the implementation of RAAT, albeit one which is triggered by some aspect of Devialet's Ethernet interface (software and/or hardware).  It is the combination of RAAT, Devialet and a GbE physical link which results in incorrect behaviour, and isolating any single part of that combination as "the problem" is perhaps premature.  Just for the sake of neutrality and balance...

A fair statement, but Devialet did acknowledge the issues, released an update a year ago that moved things in the right direction, but problems still remained.

Personally, I'm no longer experiencing any of these issues nor looking to lay blame.  But I do feel that there is still work to be done by Devialet on a couple of fronts, this being just one.  Whether any of that will happen remains a mystery.

[markush]

Wow - just did a recent test with Roon release 831 and the difference between RAAT and AIR are reasonable. It seems Roon treats the SAM setting differently - meaning needing a higher SAM % setting on AIR than ROON to be the same.
I have a high resolving HiFi system and tested this extensively.

Did someone experience the same?