Failed to connect the device. Sennheiser's third-generation microphone has no sound. The wired microphone shall be equipped with No.5 battery, so as to ensure that the audio output interface of the wireless microphone receiving box charged by power supply is connected with the audio input interface of audio. Connect the power supply of the receiving box, turn on the mobile phone, search for pairing by Bluetooth, and the indicator light of the receiving box will flash and always light up. Turn on the microphone switch, and after the whole program, you can sing as you like. The effective distance of wireless microphone is as high as tens of meters.