Up until a couple of weeks ago all of my files were shown with a preview image, including audio files. Suddenly, any new audio files I downloaded or transferred would not show an image. This includes audio files that previously had artwork showing as a preview. The audio files still have the artwork embedded. I have confirmed this by transferring the same audio files to my windows desktop and by using a mac program mp3-info. I have not installed any new programs, and I don't recall changing any settings. I have made sure that "Show preview image" is checked. Tonight, I found that if I add the audio file to iTunes, access properties, and copy the artwork, I can paste the copied artwork as the icon for the audio file. Hopefully there is some kind of setting I tripped and I can easily change it back.