Any chance these WMA files are DRM-protected files? The first time you try to rip a CD in Windows Media Player it is set to “copy protect music” in WMA format. I’d suggest unchecking this option in Tools –> Options –> Rip Music tab –> in the Rip settings box.
Did you download or rip these problem WMA tracks? If you downloaded them are the copy protected? If they are copy protected you might get them to work on the Clip by doing a Sync with Windows Media Player or WinAmp or MediaMonkey or …
Good luck.
