Ensure the USB drive is formatted to FAT32, and the file is in the root directory for the keyboard to read it properly. If this is a Ruijie Reyee Access Point:
What when you tried to use it? (e.g., file not recognized, audio playing incorrectly) RJ433161.mp3
Based on typical naming conventions, "RJ433161" suggests a file related to a musical instrument or a Ruijie networking product . Ensure the USB drive is formatted to FAT32,
However, since this appears to be a specific audio file or product, here is how to find the proper guide: file not recognized