What does the "Device Volume Level" mean

I have the Alexa skill and Sonos Voice Control enabled on my Era 100. I can set the Alexa volume level from 1-10 and the Sonos from 1-100%; so maybe I am ahead of the game.

Whenever I ask Alexa what the volume level is, it is currently saying “Device Volume Level is 2”. It has said the level is at 5,1 and other numbers before. It has no affect on the audio levels from the Era, but it makes no sense and I cannot find any other people reporting the issue.