"File format not supported" randomly appears

“I found out if you just change the format which you download from a cd from standard on window’s media player to mp3 that it works”

The default for Windows Media Player is to rip to protected WMA. The Clip Sport doesn’t support protected WMA files. I now rip CDs to 320 kbps mp3. I used to rip them to 256 kbps mp3.