The USB Flash Drive Is Not Recognized or Its Files Cannot Be Played?

Possible Causes:
- The USB flash drive is not formatted as FAT32.
- The audio files are in an unsupported format.
- The USB flash drive exceeds the supported capacity of 128 GB.
- The USB flash drive does not meet the device's power requirements.

Solutions:
1. Format the USB flash drive as FAT32. Back up your files before formatting, as this process will erase existing data.
2. Make sure your audio files are in MP3 or FLAC format. WAV, AAC, APE, WMA, and other unsupported formats cannot be played.
3. Use a USB flash drive with a capacity of 128 GB or less.
4. If the drive is still not recognized, try another compatible USB flash drive.