Welcome to the forum, and Happy Good Friday to you too.
Let's start with details of the Clips in question, the ones, that loose sync. I assume that they are muxed (both an Audio and a Video Stream in one file). Is that correct? When you look at those problem Clips, is there a little red/white rectangle with numbers and either a -, or + sign?
As DVD's are MPEG-2, things can happen in the Transcode. This seems to happen more often, when one has an MPEG Audio, and/or Video source. I have experienced similar, in that on my Timeline (PrPro) everything was in perfect sync, but on the DVD, the went OOS (Out Of Sync). I struggled by "guessing" on the amount of OOS, and never could get it right. To fix things, I used the Render/Replace (not sure if PrE has that function directly), which renders the MPEG Audio to PCM/WAV, adds that to the Project Panel, then replaces that original Audio with the new WAV file. One can do that manually, by using the WAB (Work Area Bar), and Exporting/Sharing the Audio only as a WAV file @ 48KHz 16-bit, then Importing that, and manually replacing the MPEG Audio portion of the Clip. To unlink the Audio & Video in a muxed file, one can Select it, and from the Toolbar, choose Clip>Unlink, or temporarily unlink by Alt-clicking on the Audio portion, and Deleting it. In PrPro, Render/Replace is accessed by Rt-clicking on the Audio portion of the Clip. Just not sure if newer PrE versions have added that. Since it is an easy "one-step" operation, it is obviously easier.
For addressing OOS, this ARTICLE goes into detail, but am not sure that it will help, since playback in your Timeline is perfect, and it is just the Transcoding, that causes the problem. Still, might be worth a read?
The "skipping" music bed is next. Which Audio Track is it on? The reason that I ask this, is that at least through PrE 9, there have been problems reported if the Soundtrack, or Narration Track (both Fixed Audio Tracks) are used. This seems Project-specific, as those problems do not exist for all Projects, and definitely not all users, but they have shown up. The "trick" has been to just Move the music Clip to a free "regular" Audio Track, even one needs to be created for it.
Good luck, and wish that I had something concrete for you, other than "been there - done that."
PS - one more thought on the skipping music: burning to high-quality blank media is strongly recommended, and the best are Verbatim, Taiyo-Yuden and Falcon Pro. Lower-quality blank media can cause skipping, hanging and even failure to play. One would likely hear skipping most in music, and might not pick up on it, with dialog. Just a thought.
Message was edited by: Bill Hunt - Added PS
Wow and thank you so much. I'll work on those pieces and let you know. It's
funny how all the other pre-final discs of this project were fine, though.
Thanks for the generosity of your time.
Be well and Happy Easter and Spring!
Hope that something helps. I wish that I knew more about the "how," when things go OOS, but it has always happened to me with MPEG Audio & Video. The intermittent nature has keep me from finding a definitive "common thread." It just seems to happen some times, but not others, though the Imported, edited material, and the output seem to be the same. A mystery, at least to me.
Good luck, and many happy things for you too!