How to Increase Gain on a MacBook
- 1). Connect any external sound devices to the MacBook, if necessary.
- 2). Click the "System Preferences" icon in the dock.
- 3). Click "Sound."
- 4). Click "Input" or "Output," depending on the device type.
- 5). Click the device in the list.
- 6). Drag the slider to the right to increase the gain.
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