Procedure

Every time a route is setup between two devices, Dante configures what is referred to as a "flow". Dante devices have a limit to the number of flows that can be transmitted and received. The limit is based on the specific Dante hardware the device is built around.

If all flows are already assigned when trying to set up a subscription, the subscription will fail. This is indicated by a red error icon. Hovering over the red icon will result in a pop up message stating that no more flows are available as shown below.

If the receiving device has run out of flows, there is no easy fix. The only option is to try add a channel to an exiting flow from another device and then somehow arranging for that device to be an intermediary for the audio you need, essential sending audio from C to A by sending it via B.

However, if the transmit device has run out of flows, to sent to more places than the available flows, Dante has another method of audio transfer: Multicast

With multicast, you can use a single flow to send the same set of audio channels to theoretically an infinite number of receiving devices. The downside is the affect on the network as multicast packets are sent to every device on the network, regardless if the packets are needed by the recipient device (even devices that are not Dante audio devices will receive them). Network switches do have a way to handle this however. To reduce the impact of multicast packets, IGMP snooping should be enabled on the switch.

To transmit a multicast flow, it must be manually set up on each device in Dante Controller as shown below.
 

Once a multicast flow is set up, the red icons in Dante Controller will change to green showing the flows have been assigned.

Below is a video showing how to setup a multicast flow.