Operating two RME Digiface Dante together at 96kHz (and IPv4 Multicast blocking)
 
 

Operating two RME Digiface Dante together at 96kHz (and IPv4 Multicast blocking)

August 2, 2025
HOWTO, configuration
Dante, Audio, IXDP

Motivation #

The Digiface Dante is a lightweight, portable audio interface, combining Dante network connectivity and features with everything that RME is famous for: USB 3, MADI, TotalMix FX and outstanding options in both USB and stand-alone operation.

A single Digiface Dante at 96kHz provides 32/32 i/o channels, which can quickly become unsufficient with a few external analog audio hardware connected (our analog summing mixer alone “consumes” 16 input channels and 4 output channels).

This post explains how to setup a dual Digiface Dante audio interface providing 64/64 i/o channels in total (at 96kHz) - all available within TotalMix without any further configuration actions.

That this is working as expected is no suprise, but I was unable to find any resources that explicitly describe the same setup - so here it is.

Dual Digiface Dante Dual RME Digiface Dante in Operation

Physical Connections #

  • The lower Digiface Dante is connected via USB3 to the Mac host (in our case it’s currently an older Mac Pro “late 2013”). It’s important to connect directly avoiding any USB hubs in between.
  • The upper Digiface Dante operates as a standalone MADI to Dante Bridge.
  • Both have the external power supply connected.
  • Two short Sommer 75 Ohm BNC cables connect the two units together.
  • Primary 1 of the lower unit connects to the local Dante Ethernet LAN.
  • Primary 1 of the upper unit connects to the primary 2 of the lower taking advantage of the built-in switch functionality.

Updating both Units RME USB Series Flash Tool #

  • Both units need to be updated with the RME USB Series Flash Tool.
  • This requires connecting each Digiface Dante with USB (the second unit is disconnected later).

RME USB Series Flash Tool

Settings for the MADI interconnection 96 kHz #

Both units need to be configured once with these settings (which specify the MADI connection in between):

Fireface USB Settings

After this, the upper unit is unplugged from USB and operates as a standalone MADI-Dante bridge automatically.

Example Dante Controller View #

This is our Dante Controller view:

Dante Controller

RME TotalMix #

And, voilà - TotalMix shows 64 channels in and 64 channels out (the channels of the main unit are labeled “DA” for “Dante Audio”, the channels of the MADI bridging unit as “MA” for “MADI Audio”):

RME TotalMix

Dante IPv4 Multicast, any Problems? #

Here’s a Wireshark session focusing on the IPv4 Multicast communications:

Dante Multicast Example

There is an issue with WLAN access points (which applies to Dante networks in general):

  • When there are WLAN access points in the same flat LAN, PTP v1 Multicast packets are also propagated on the wireless network with high priority (DSCP Label CS7).
  • The AVM WLAN Mesh negotiations are also using IPv4 multicast.

The unwanted effects are:

  • The AVM Mesh breaks, single access points are loosing their mesh membership.
  • Wireless clients have no “internet connection”.

Dante Multicast separation with IXDP #

An IXDP bridge separates the LAN in two parts and blocks only IPv4 multicast packets. The required RPCL configuration setting is this:

0 mcastdrop.enable
1 mcastdrop.enable

Resources #