Can't select audio clip even though it's there

I have an audio clip attached to a game object. It worked, I did some cleaning up, put all the audio files in a folder with in the Unity interface called sounds and I saved the scene. When I reopened the scene the "Audio Source" for the GO in inspector said, "Missing (Audio Clip)" so I selected the drop down and reselected the sound file. I figured since I moved it to a folder something had gotten messed up. After I selected the file the AudioClip immediately goes to none?! So I moved the audio files back to were the were when the worked and the same thing, I select the clip and it reverts to "None (Audio Clip)" Any ideas?