Standby mode low-power-consumption flow media automatic play device

The automatic play back device includes sensing circuit, circuit for playing stream media, and MCU. In state of stand by, the invention can sense external stream media device, and outputs audio signalonly for audio/video file carried when playing operation is carried out automatically under low power consumption mode. After pulling out external stream media device, the invention comes back to previous original stand by state automatically. Thus, the invention reduces power consumption greatly, and saves electrical energy.