RoonServer 'Critical' Errors in RoonServer_log.txt

Server setup:

  • Roon Server Version 1.3 build 218 stable (64-bit)
  • Ubuntu Server version 16.10 on VMware Workstation 12 Pro (latest build); host computer is running Windows 10 64-bit
  • 8GB memory, Core i5-3570K
  • Storage is an 800GB VMware disk image residing on the host computer’s spanned 12TB volume (all Western Digital ‘Green’ series disks). 1007 albums (FLAC, ALAC & Tidal), 22571 tracks
  • Gigabit Ethernet
  • 150Mbps (upload & download) fiber optic connection to Internet


  • RPi 3 running Raspbian GNU/Linux 8 (jessie)
  • Roon Bridge Version 1.0 build 81
  • HiFiBerry DAC+ Pro
  • 100Mbps Ethernet


  • MacBook Pro (late 2013); macOS Sierra 10.12.4
  • Roon Version 1.3 build 218
  • 802.11n 5GHz Wi-Fi

Issue: Frequent dropouts on the HiFiBerry DAC+ and loss of connectivity to the Roon Server from the MacBook Pro controlling playback. Playing a 24-bit, 96kHz FLAC file this morning, but this problem occurs with any content type (especially Tidal).

Lots of errors in RoonServer_log.txt similar to the following (I can send the whole log file if needed):

04/14 10:57:05 Critical: scx: in OnExit: System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values.
Parameter name: index
  at System.Array.InternalArray__get_Item[T] (System.Int32 index) [0x0000c] in <a8460a77e67a430a8486a9751162e5f4>:0 
  at (wrapper managed-to-managed) Sooloos.Broker.Transport.TransportTrack[]:System.Collections.Generic.IList`1.get_Item (int)
  at Sooloos.Broker.Transport.TransportItem.get_CurrentTrack () [0x00000] in /home/roon/roon/Broker/Core/transport/transport_items.cs:278 
  at Sooloos.Broker.Transport.Zone.get__CurrentTrack () [0x00018] in /home/roon/roon/Broker/Core/transport/transport_zone.cs:732 
  at Sooloos.Broker.Transport.Zone.ev_threadexit () [0x00491] in /home/roon/roon/Broker/Core/transport/transport_zone.cs:574 
  at Sooloos.Broker.Transport.Module.ev_threadexit () [0x00d58] in /home/roon/roon/Broker/Core/transport/transport_module.cs:532

The RAATServer on the RPi generates dropout error messages in /var/roon/RAATServer/Logs/RAATServer_log.txt when this happens, and the MacBook Pro loses its connection to the Roon Server at the same time.

Any help would be appreciated,



Hi @Adam_Woodbridge ---- Thank you for report and my apologies for the troubles here. I would like to grab a set of your logs from you, but first may I kindly ask you to please describe your current network configuration/topology. Having insight into any networking hardware you may be implementing would be good information for us to have.

I want to have a complete understanding of how your devices are communicating and what tools you are using to make those connections possible.

Looking forward to your feedback!

Hi Eric,

The RAAT Server log is here:

And the Roon Server log is here:

I have switched gigabit Ethernet throughout the house, but in this case the Server and RPi/HiFiBerry DAC+ are plugged into the same TP-Link TL-SG108E gigabit Ethernet switch. The server has an Intel 82579V Gigabit Ethernet chipset. There’s about an 8’ separation between the RPi and the Server.

On that same switch is my router (FreeBSD; custom-built) which in turn connects to the telecommunication company’s bridge unit and from there out to the Internet.

As an aside, two days ago I did try moving the Roon Server out of the Ubuntu Linux virtual machine, putting it directly on the Windows 10 machine running VMware Workstation: that made no difference.

Thanks for your prompt reply,


Also, the Ubuntu Server is “stock”, with static IP addressing. It’s running nothing else besides the Roon Server daemon, and I’ve made no kernel modifications (through sysctl, for instance). It has about 2% CPU utilization streaming 24-bit/192kHz FLAC files.


I haven’t seen these ‘critical’ errors since taking the core out of the VM and putting it on bare metal (Ubuntu Server, same physical hardware as the original Windows 10 host).

Very strange.


Hi @Adam_Woodbridge ----- Thank you for taking the time to follow up with me and answering my questions. Confirming that I have received your logs.

This most recent observation is an interesting one. Just to make sure I am understanding this correctly, did you reassign your core to another device or did you actually swap the hardware out of the previous server and put it into a new “box”?



I took the physical server (Core i5 3570K) running Windows 10 (and Ubuntu Server under VMware workstation), completely erased Windows and installed Ubuntu Server 16.10 (now upgraded to 17.04).


Hi @Adam_Woodbridge ---- Thank you for clarifying that for me.

This is obviously a bit of a shot in the dark, but being as things are now stable with Windows gone and Ubuntu Server 17.04 in it’s place. Did you by chance notice a Win10 update previous to this behavior occurring?



It did have the Windows 10 Creators Update installed.