3.5mm stereo audio ground isolator module common anti-interference signal generator XH-M372 Audio isolation transformer is a transformer used for audio signal transmission between systems or equipment, which can avoid some problems caused by cascaded audio systems and realize the safe transmission of audio signals. Specifications Model: XH-M372 Item Type: Isolation Module Material: resin Model: XH-M372 Input / Output: 3.5mm headphone jack Dimensions: approx. 53 x 32 mm  This product is an audio common ground isolator, effective for noise caused by the common ground of the audio source and the receiving device. Since the grounding points of the two devices are different, common ground noise may be generated. In the car audio there is some kind of audio interference, like a whistle, the frequency of this noise will change with the engine speed. Therefore, this product can only eliminate the noise and current noise caused by common electrical and common ground products.