Sound is distorted.

1) Is the [MASTER LEVEL] control set to the proper position?

Adjust the [MASTER LEVEL] control according to the connected devices.

2) Is the [HEADPHONES LEVEL] control set to the proper position?

Adjust the [HEADPHONES LEVEL] control according to the connected device.

3) Is the level of the audio input to the [MIC] input terminal set to an appropriate level?

Set the level of the audio input to the [MIC] input terminal to an appropriate level according to the connected device.