Crestron + Roon Nucleus == problems

Test installation details are:

  • Nucleus as Roon Core and Audio zone

  • Intel NUC/Win10 as second Audio zone and Controller

  • iPad mini 4 as Controller and CrestronAPP

  • Crestron CP3N (latest firmware) - with demo program from your website

  • My Win7 PC for XPanel and Controller

  • All devices connected to the same 1000 Mb/s switch (Ubiquity)

Sometimes everything works and is controlled perfectly from Roon App (iPad),

but here is the list of my current problems .

1. GUI on XPanel and iPad works VERY SLOWLY.

Please, see some videos:

Nucleus is playing content from USB stick plugged in its port.

Browsing panel may be empty with “busy flower” indicator for 1-2-5-infinity minutes. Now playing metadata usually comes in 30-60 seconds…

On the same configuration Autonomic MMS works with no lag.

2. No connection after restart.

After Crestron program reset/restart/reboot Crestron Extensions disappear from Nucleus (see last video).

Crestron does not control Roon anymore. Nucleus restart / Roon server restart is required to fix the problem.

We need reliable 24/7 installation working without asking Network Administrator for support after every power cycle.

3. Processor load is too high

Roon software (as a Controller) on my Win7 PC takes 5-10 % of CPU and heats it as when I work with heavy video processing apps or games. Is it OK for application only showing text & 1 album art picture??

@SteveSilberman and @support please help me. Screenshots are in the following posts

And Please help me as soon as possible.


Hello @Maxim_Balitskiy,

Thanks for contacting support regarding this issue. Let me try to address a few of your points:

  • I noticed that you are usng a CP3N processor, which contains a dedicated control subnet port. In our experience, we have noticed that processors with dedicated Control Subnet ports (CP3N/AV3) sometimes have issues establishing proper communication with the module. We are investigating possible workarounds for this, but none have been released at the moment and the internal NAT in processors with Control Subnets seems to cause issues with Roon operating properly.

  • You mentioned that you have all your devices connected to an Ubiquiti switch. We have seen that the “flow control” setting on these switches sometimes need to be enabled for Roon to operate properly, please take a look at these threads:

  • If you have any other firewall applications on your Ubiquiti switch or Windows 7 PC, I would try temporarily disabling them as well to see if performance improves.

  • Since the “Explore” menu is not loading properly at times, this could indicate that either that there is something blocking proper communication to the Roon module or that the module wasn’t able to establish successful communication with the Nucleus. I would perform a “Recompile-All” in your SIMPL program and try uploading the module again to the processor.

  • Yes, resetting the program will cause Roon to stop communicating with the module. I am noticing some strange behavior when just pressing “Reset Program” in debugger as you did in the last video and I have asked QA to take a closer look at this behavior, I appreciate your patience while this request reaches their queue.

Please let me know if any of my above suggestions help and I will be sure to let you know once I hear back from QA.


Dear @Testing_Acc_NO
Thanks for immediate response.

Of course, I:

  • have read about dual eth issues - I do not use internal control subnet, only ethernet
  • have recompiled-all
  • disabled anti-virus / firewall
  • reset/reboot/set-defaulted everything

I have no problems (yet) with streaming, only with control from Crestron.

I understand that when I restart program on crestron, communication is temporarily broken. But it should re-establish automatically, without re-booting Nucleus.

AFAIK Crestron App (media player widget) communicates with control system & with controlled device - it works perfect with Denon HEOS, Autonomic etc. All with my test installation (not all simultantously, of course).

I will try some stupid switch (like D-link or Zyxel) - but shure it won’t help…

Tried unmanaged Zyxel switch - no changes.

PS. and every time I send program to CP3N, I have to re-start Nucleus :frowning:

Hello @Maxim_Balitskiy,

Thank you for verifying the behavior with another unmanaged switch. In our internal testing, the issues I described for processors with control subnets seem to be persistent even if you are not making use of the Control Subnet port and only the LAN port.

With that said, I do have one other option available for you here – We have an unreleased Crestron build that is still being tested by our QA team, but which may help with the issues you’re describing.

If you’d rather wait until we have an official build I can let you know when it’s released, but if you’re interested in testing this pre-release build, I can send you the details – we’d love to hear your feedback.

Just let me know if this is something you would be interested in and I can prepare the sample.


Hello, thank for your reply, let’s try beta, waiting for instructions.

Hello @Maxim_Balitskiy,

I just PM’d you the information for the Beta Module. Please let me know your feedback for it after you give it a try!


Hi @Maxim_Balitskiy,

We have just released Crestron Build 8 which addresses the issue for communication with AV3 and processors with subnets:

Roon Crestron Module Build 8 is Live! Home Automation (Nucleus Only)

Hello Everyone, we have just released Crestron Build 8 tada Have a processor with a Control Subnet? Wait no more and make the upgrade to Build 8! Full details for this release can be found on our KB page: Release Notes: You are now required to place the Nucleus IP address in the RoonSystemModule symbol and it is recommended that this IP does not change Added support for processors with Control Subnets such as CP3N, PRO3 & AV3 Improved TIDAL Search function…

Please give the updated module a go and let me know how it goes!