1, audio format is not supported, so it cannot be played. You can use a video converter or a format factory to convert audio formats.
2. The voice can't identify the file formatting system of the U disk. Generally speaking, the sound system can recognize FAT32.
3. The virus in the USB flash drive prevents the stereo from reading the correct information in the USB flash drive.
4. The flash memory chip of the U disk has bad blocks, and the sound is unrecognizable.