I believe some of the files on the internal SD card are not easily read/copied. I remember several years ago there was a Kenwood specific forum (that's now gone) which had a long discussion about the internal SD card contents of the newer Kenwood head units. I dont think anyone was ever able to copy successfully all the files on the internal SD card. Of course someone may have accomplished this and I just missed it. It wasnt as simple as someone taking their SD card out, copying the files to a computer and saving those files to a new SD card.