iOS - ReplayKit: When broadcasting from a ReplayKit enabled game on iOS, your broadcast will include the in-game audio by default, at the volume level set on the device. To enable microphone functionality, tap the microphone button to toggle it on.

Android: When broadcasting from the Mobcrush Android app, the microphone is used to broadcast both your voice AND in-game audio. In order to have game audio in your stream, you must enable the microphone, which is on by default. If this is frustrating, we understand, but unfortunately this is a Android operation system level limitation we've can't work around :(

Mac App: When beginning to broadcast, you will see that there are two buttons that say MIC and the other GAME. When you start to broadcast those audio options are set in the middle, meaning when you do broadcast some audio from your device's mic will be picked up along with some game audio.

To have only game audio, simply press the GAME button repeatedly until it is all the way blue and there is no color left on the MIC button. The same works should you wish to have only MIC audio rather than GAME audio, but just having MIC all the way blue.