I. Why Do USB Decoding Data Cables Affect Sound Quality? For front-end audio decoding devices, especially the USB dongles / decoding amplifiers without batteries, there is a power-on sequence for the operation of USB identification, audio bridge chips as well as the DAC, which involves different voltages and currents. If the output from the mobile phone end is extremely stable and abundant, it could be assumed that USB cables would have little impact on the subsequent devices. However, this is not possible. Not to mention that the OTG output judgment voltages of different brands of mobile phones are different. Even…