Creating a podcast in garageband with background music

I have created a podcast in garageband using background music from itunes. When I pause to take a breath, the volume of the music increases sharply. When my voice resumes, the volume of the music decreases. It creates a jarring effect.

Is there anyway to stop this happening during short pauses?

Also is it possible to fade the music out at the end of the track?

Thanks for your help