That’s what I thought I had recalled. 
Got my sport clip in 2014, wanting maximum holding capacity, though recognized I already had more than 28GB of music, so I got an 8GB sport, and later installed a 64GB sd card. Before adding it, I noticed a limit for the number of ‘favorites’, discovered the usefulness of ‘folder’ option, always playing with ‘random’.
I play many thousands of songs, and the 64GB disk continues to work just fine!
