I occasionally get this error message - a typical scenario is that while playing an album I notice that songs are missing. In sensitive IEMs I hear a slight cracking noise when the song is accidentally skipped. Going back to that song it plays without problems. Another scenario is when quickly skipping through albums with high-res files, i.e. large files. It might be the memory card being too slow.
Noodles, are you playing your songs from the internal memory or from external card?