QSC Q-SYS Network Support Checklist

Before contacting Q-SYS technical support, please answer the following questions:

1.Was the Q-SYS system operating properly before this support call, or is it a new deployment?
2.Is this a dedicated network for Q-SYS only, does it share the network with other AV equipment or is Q-SYS running on a fully converged network shared with AV and other IT devices?
3.Can you identify a trigger that can cause this issue to occur on a regular basis?
4.Is the issue tied to a specific network location (IDF/MDF) and/or time of day?
5.Identify the version of Q-SYS Designer Software for which the system is running?
6.What is the make/model of the network switches used in your Q-SYS deployment?
7.Download the Q-SYS System Information file (a.k.a. Q-SYS Log Archive).
8.What type of network deployment are you using (Q-SYS LAN A only or both LAN A and LAN B for redundancy, the number of switches and link speeds between switches)
9.Have you enabled verbose mode within the Q-SYS design file for Q-SYS devices and AES67 status blocks and captured verbose those statistics after a period of time where the problem exhibited via screen shot (example: Windows snipping tool).

Prior to contacting Q-SYS Support, please check the following common problems:

Having more than one Gateway configured on a Q-SYS Core processor (or other Q-SYS device) is not supported. Please ensure that only one network interface has a Gateway configured. If making changes to the Gateway and/or creating static routes, please reboot the Q-SYS Core processor for the changes to take effect.
Q-SYS devices do not support Ethernet tagged frames (802.1q, ISL or other such VLAN tagging technology) on the switch port where Q-SYS connects. Ensure the switch ports are configured as access ports (edge ports) with no possibility of VLAN tagging.
Ensure LAN A, LAN B, AUX A, AUX B ARE NOT using overlapping IP networks.
Ensure LAN A, LAN B, AUX A, AUX B ARE on different VLAN’s or switches.
Make sure that you have selected the correct Q-SYS DSCP settings for your project type (Q-LAN only, Q-LAN plus Dante or Custom QoS values). Verify those QoS values are configured on all switches and switch ports where time sensitive media traffic must pass.
  • Q-LAN PTPv2 is marked EF (46) and needs to be placed in the highest priority queue (Strict Priority Queueing is required). The Audinate QoS option changes this value to CS7 (56).
  • Q-LAN Audio is marked AF41 (34) and needs to be placed in the 2nd highest priority queue (Strict Priority Queueing is required). The Audinate QoS option changes this value to EF (46).
  • Q-LAN Video is marked AF31 (26) and needs to be placed in the 3rd highest priority queue (Strict Priority Queueing if possible).

Q-LAN end-to-end latency is measured in the low microseconds level and places strict performance requirements on the network regarding latency, jitter and packet loss. Network switch interfaces need to be 1GbE or faster, exhibit no errors, and jumbo frames should not be used on the same VLAN, Subnet or shared Trunks.
Deployments that use multicast data for transport of audio and/or video require proper IGMP Snooping v2 configuration with a single IGMP Querier per VLAN / Subnet.
End-to-End latency is a key factor in successful Q-LAN deployment, each switch hop adds extra latency to the path. As a result, keeping the lowest possible switch hop count between Q-SYS devices yields best results. Keeping the switch hop count to 5 or less will help, 5 and above may require high performance switches with very low packet forwarding time.
Limiting the size of the broadcast domain in an IP subnet to 254 devices (/24) is recommended for best performance. Try not exceed 510 devices (/23) per IP subnet due to the amount of overhead and broadcast traffic that will be contributed to the subnet with that number of devices.
3rd party AES67 devices may not be able to support Layer 3 network deployments and may affect Q-SYS performance in a Layer 3 network deployment.