With 2 Elements, controls for Mixer aren't working OR they're controlling the wrong Mixer

This post addresses possible issues when using 2 Elements at the same time and routing audio through the low-latency mixers in the Element Control app. If you aren't using 2 Elements together or if you are, but you're not using any of the mixers built into Control (Element latency is low enough, the majority of use-cases don't require using these mixers), then this post does not apply. Issue(s):
  • Audio not showing up on correct Mixer Master meters-OR-not showing up at all in the Mixer Master meters.
  • Mixer controls, such as faders, pans, mutes, and solos do not affect the audio
  • Mixer controls for one Mixer seem to be affecting another Mixer
  • Assuming both units are showing up correctly in the Element Control software, verify that the input signal is showing up on the correct channel(s) meters at the top of the Control window.
  • The next thing to check would be the optical cables that connect the 2 units. These cables are essential for properly clocking the units together and transferring audio back and forth across the built-in low-latency mixers of each unit. If the cables aren't connected properly, you could experience the issues above or even only one unit showing up on your Mac.
  • Double-check that you have connected optical cables from Unit A's optical output(s) to Unit B's optical input(s) and from Unit B's optical output(s) to Unit A's optical input(s). Remember that if you're using 2 Element 88s, you will need 4 optical cables since there are 4 ports on each unit. Make sure that the cables are connected correctly. It is very easy to accidentally connect them in the wrong order.
  • If you need to disconnect/reconnect or switch around any optical cables, make sure to restart the Mac after doing so.