Roland GO:LIVECAST Live Streaming Audio and Video Studio for Smartphones and Tablets - Manual (Page 9)

Muting the mic
When you’re not using the mic, you can mute the mic audio by
pressing the [MIC MUTE] button to make it light.
Connecting an Audio Player or Keyboard
Audio player Keyboard
MIN MAX
1.
You can use a separately sold audio cable to connect an audio
player or keyboard to the LINE IN jack.
Make the connection via a 3.5 mm stereo mini-plug.
2.
Use the [LINE IN] knob to adjust the volume of the connected
device.
* To prevent malfunctions or damage, be sure to minimize the volume of all devices and
turn off their power before making connections.
* The sound that’s input at LINE IN is mixed to mono.
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