What do the Min and Max volume settings do, and how do they work?
Both of these settings are absolute volume levels. A volume level of 0 means that the signal level coming into the switch is the same as the signal level going out. Each step of one of the settings is a 0.5dB change. So a setting of 1 = +0.5dB gain, and -1 = -0.5dB loss.
So the default values are 24 = 12.0dB gain, and -120 = -60dB loss.
These values set the range of the volume control. The volume setting is between 0 and 100. When set to 0, the audio always mutes, regardless of these settings. These settings represent the volume levels between 1 and 100. 1 = Set the volume to the level indicated by Min Volume. 100 = Set the volume to the level indicated by Max Volume. All other settings are a percentage between these two levels, for instance 50 = Set the volume to a level exactly half way between Min Volume and Max Volume.
The use of the Max Volume is pretty straight forward. Any user of the switch cannot set the level above Max Volume, this can be used to limit volumes at specific zones.
The Min Volume use is more subtle. If you are in a quiet room, you can turn down the volume and still here audio way down into whisper levels. In a case like this you would set the Min Volume to a large negative values, since this will allow you to turn the volume way down.
If you have speakers in the backyard, you might not hear much once you turn the speakers below 50% because of all the background noise, this is irritating because now half the volume is wasted, once you get below 50% nothing happens. And if the volume level starts all the way down, it can feel like it's not working as you hold the volume button down between 1% & 49%, waiting to hear something. In this case you can turn the Min Volume up until you can actually start to hear something at around 5% or so. Now you have the complete range of the volume control from 1% to 100%, and the sound fades out below 5% like it should.
Note: Changes to this command should be backed up in case of power failure by going to Composer's Action Tab and pressing the "Backup Audio Settings (except volume)" button.