Predecessor to slotMusic? It sounds like the same concept. “The Disney Mix Micro plays MP3/WMA, Disney Mix Clips, and SD/MMC cards. Just plug a Disney Mix Clip (sold separately) into the MP3 player - you don’t even need a computer!”
I took a look at the manual, and the player has repeat playback and random play functions, but a 2gb limit on the SD expansion slot. It’s is currently on sale for $4.99 online.