MERGING+NADAC Mute - Unmute

Problem

Use the MERGING+NADAC Power button to mute or unmute your MERGING+NADAC outputs

Solution

Quickly pressing the MERGING+NADAC Power button will mute the MERGING+NADAC outputs.
To unmute, quickly press the MERGING+NADAC Power button again : you will go back to your original level, unless this one was above -20 dB 
This does not apply to Headphones mute/unmute

You can also turn the MERGING+NADAC Rotary button to unmute and gradually increase your volume level.