The frequency of the operation can not be completed generally because the receiver's infrared emission window and the microphone's infrared receiver window is not right, first find the receiver's infrared launch window, usually in the lower left corner of the receiver, the lower right corner or the middle position, Please refer to the instructions, the microphone is generally in the middle of the display and power switch position, different models please refer to the instructions, the receiving window and the launch window at the general distance of 50 cm can be.