November 19, 2020

Apple Mac - Mic Level Automatically Changing

When home, I work from a 2015 MacBook Pro using a Rode NT-USB Mini USB Mini mic on this stand, with some Sony MDR-V6 headphones. This is probably a bit overkill for Microsoft Teams meetings, but I lean into the absurdity of it. I like being on video with a fuzzy mic right in front of me.

The actual reason I have a mic is to record “interviews” with my two daughters. This is something I have done since they could talk.

I noticed early on when working from my Mac that the mic seemed to behave differently when I was on Teams calls. Sometimes the mic level would go down to zero and nobody could hear me, but more often the mic level would jump to maximum and all background noise was extremely amplified.

I started paying more attention to the audio input setting on my Mac. I could actually see the input levels jump around on their own, but had no idea why. I just dealt with it for weeks. It was workable, but I had to make sure there was absolutely no background noise if I wanted to use my mic.

Then I started recording a podcast with my friend. In our first recording I could really tell that my mic level was way too high. I sounded terrible. This led me to start googling the internet to see if I could find anybody else with similar issues.

Right out of the gate I found this article by Dan Moren… The mystery of OS X’s haunted input volume slider – Six Colors. This describes my problem exactly. He seems to pin down that it is app specific. For me, it seemed to be happening on multiple apps… well at least Microsoft Teams and Google Chrome. I use Audacity to record locally sometimes. That app wasn’t having any issues at all. I am able to adjust my mic level in the app and it is maintained correctly.

I continued my search. I read on a random thread that creating an aggregate device seemed to help with the issue. This process was easy to do, but difficult to understand exactly what was going on. The behavior of my aggregate device seems odd. I don’t have the ability to set the input levels at all. It is like it isn’t even recognized as a mic. I played around with every thing I could think of in the interface and ended up going back to just creating a duplicate of my Røde mic with no other devices included in the aggregation.

This appears to have done the trick for Teams. Every time a meeting starts I get a warning that says my mic volume is low, but it works and everybody says they can hear me just fine. I also don’t notice background noise nearly as much in my headphones.  When I start speaking my voice isn’t so lound loud and harsh like it was before. [1]

My next step is to do a test recording in our podcast software in Chrome to see how it sounds. I am hopeful that it resolves the issue there as well. It is still frustrating that I am not sure what is going on and why it happens, but I will just be happy to have it over with.


  1. Typically my voice would start out loud and harsh in my headphones, but them immediately go down to a “normal” level.  ↩