That's what I'm afraid of 
I was hoping I was going to hear something like "the algorithn for bitrate doesn't like 5, try 4.8" or something like that..
I re-encoded as I noticed the default for Encore was 23.97 and as my footage is 29.97 (and output usually is 29.97 for DVD isn't it?) I wanted to see if it made a difference. And the answer is no...
Here is the preset I used: 
Here is what came out (screen shot from playing via VLC): 
And as a frame of reference, here's how it looks when I just let Encore do it's thing automatically: 
I will try creating a new project and importing all the footage as fresh timelines, plus the main menu to access things, to see how an automatic encode changes via that workaround. Seems like an odd...bug? Lack of feature? not to be able to add things after one reaches a certain point in a project and having to start over from scratch (especially since I do a lot of tweaking of the menus by sending things back to Photoshop to get layout, highlights, etc just right and it's one of the features I love about Encore vs DVD Studio Pro or any other option I've looked at)