I ran across such a machine. We had to start using .WAV files. Since it's easy enough to convert, they did that.
-> You post has so little detail. I can't tell if the machine you use has a system restore feature.
Everytime I import an MP3 song into Windows Movie Maker into the video, it wont play the song, but anything else besides the audio. Cna someone help me fix this? It wont play MP3 audio anymore, but it used to...