1. Burning an audio CD from your MP3's

2. Make sure your WMP has the right codecs. The earlier versions did not come with an mp3 codec. See CODECs list and alternate players for Movies. For mp4/m4a I believe you need a codec like 3ivx (click on link). You also need to enable the codecs in WMP's options. Using windows media player. You could also try another burner program like iTunes