SC2 by default is accessing the microphone and you can’t disable it.
It’s been discussed before here and here. and in a few other places.
This is what I tried:
Disabling voice chat in the battlenet app.
Adding parental controls to my account to disable the voice chat.
Adding “voicechat=false” to viarbles.txt in both account and general settings.
The only things that work are disabling the device or disabling mic access to all desktop apps. Both of these are not desirable as they make your mic unusable.
Windows will show the Starcraft II client is using the mic even after the voice chat removal. Nothing voice related is being transmitted by the game even though it shows the exe is using the mic.
There is no indication that this functionality will ever be changed, but reporting it as a bug in the Bug Report forums is the correct thing to do in this case.