I just finished QuickTime update to 7.1.6, the volume control in the bottom left corner of the player window is at full volume, the wndows volume control is all the way up and I still don't have any sound in segment 3 either. Where are we supposed to make the change in QuickTime to get the volume back?
Okie dokie, I had to un-install QT 7.1.6 because the update program kept saying that 7.1.6 was the latest and greatest. I then downloaded the latest version 7.2 and installed it without a hitch. Video #3 now plays fine.
Just wanted to share in case someone needs the information.