Lenovo M0520 Guia Del Usuario página 9

Audio device input connection
Connection
1、 Before connecting or disconnecting, first unplug the USB cable and shutdown
the power to the speaker system. Failure to do so may cause malfunction or
damage.
2、 Ensure that the main audio cable is correctly connected.
3、 All cables should be connected firmly. Loose connection may cause muted
audio or noise.
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