Question: Multi Cam Audio muted on Camera 2 & 3

I have a 3 camera set up where I used the Assembly workspace to load all of my tracks for a concert.  The audio of Camera 1 plays fine, but the audio for tracks 2 & 3 are showing in the timeline, but it does not play - the audio levels beat bar moves, but no audio plays when selecting that track and muting the track 1 audio.  How do I un-mute track 2 & 3?

Thanks in advance for any assistance!

Ray