Problem: No audio from videos (.mov files) burnt in iDVD

Problem: No audio from videos (.mov files) burnt in iDVD
Originally I imported videos (.mov files) into iphoto and while in iphoto I clicked on SHARE and then SEND TO IDVD. My videos were then formatted properly and burnt in iDVD. Everything was fine. I did not need to convert the .mov files.

Then I needed 2 more copies and went to iDVD where I saved the project and then using the saved iDVD project, I burnt 2 copies. Both copies have no audio for the videos. The audio is fine for the theme and then you click on the title and the video starts just fine but there is no audio. When I click the audio button, it says the audio is off. Also, in iDVD under SETTINGS, it is checked where it says "Duck audio while playing movies." Is that setting causing this?

So, are you not supposed to save the iDVD project to make additional copies? Should I go back and make each copy separately like I did the first time? Thanks for your help. I am running a Macbook Pro with Snow Leopard v. 10.6.8