Some parts of an audio track playing.

I have adobe premiere cs6. When I try to add a second audio track on top of what is already there, it doesnt't play some parts of it. It will only play my friends voice and not mine. I will add a picture of the window to show what I have.In the picture, it has the waveforms for my friends voice, but not mine. In the actual video clip, I can hear my own voice. Any help is appreciated. The track that does this is the Minecraft track. Not the Go Cart.mp3

Thanks,

Michael