i figured it out. thanks Antonio...your post helped point me in the right direction. i didn't remove any audio with DVD shrink, but when i went to burn it using Nero, it automatically unchecked the box for the main audio file. once i checked that box, it burned a good copy with sound.
the only minor thing is i burned 5 DVDs and 4 turned out perfect. for one DVD, once i checked that audio file, i didn't have the option to burn it using Advanced analysis, i could only choose the Burn-at-once option. That was the least importance DVD, so i'm OK with, but it's weird that it didn't happen with the other 4 dvds.
thanks so much for your help...this is a great forum.