Mixing video and audio

I am still in the process of trying to mix the video and the audio together. The video plays fine, but when I attempt to mix it with the mp3 file, it doesn't work. I think this may be because the audio is not yet properly rendered. Another reason for this may be that our music video footage that we currently have on Final Cut Express was recorded with sound. It may be that I need to split the audio from our recorded video in order for it to work.

Today, I will again try to get the audio to play with the video.

Also, we should have the rest of our music video filmed soon so we will be ready to edit.