Loading might take a long time if the folder is deep or if it contains many files. It may also take a long time to read in the following cases.
・ The folder contains many folders and/or files other than music files.
・ Data fragmentation occurs.
In such cases, use another USB Storage Device or copy data from the USB Storage Device to your PC/Mac, reformat the USB Storage Device, then transfer only the music file again.
*All stored data will be cleared if you reformat the USB Storage Device. Check the appropriate method in the instruction manual of the USB Storage Device before doing so.