| 摘要 |
An audio device prevents an excessive volume output in a case such as when a set of headphones is replaced or a power supply is turned ON from OFF. A mute control circuit includes a switch that detects insertion of a headphone plug and a switch that detects a volume position. When no insertion of a headphone plug is detected, a mute mode is activated to output no audio signals. When insertion of a headphone plug is detected and it is not detected that the volume position is set at a mute position or near to the mute position, the mute mode is maintained, while when it is detected that the volume position is set at the mute position or near to the mute position, the mute mode is canceled. |
