After researching this issue in the forums, I found no solution in Encore, so I just wanted to share my workaround.
As far as I can tell, this is a long-lived issue, going back many years, and there's no solution in Encore. In feature-length projects, the audio goes out of sync several frames towards the end. I don't know if it's common to DVD authoring in general, or unique to Encore.
In my experience, the audio goes out of sync during the burning process. If I build a DVD image and mount it as a disk, there are no (or minimal) sync issues, and burning with Roxio Toast gives a better result than burning from Encore.
I tried burning using the Mac Disk Utility, but it always returns with an error saying that another program is using the disk image, even if the utility is the only open program. So it's Toast for me. I'm using Toast Titanium v.11.1.
If you have any other workarounds to solve the sync issue, it'd be helpful to post them here.
Why is this not being addressed by Adobe? From what I've read, this issue has been around for years, and nobody has an answer.
If I can't burn a DVD with synced audio, I don't care about a single other feature. Yeah, it's great that I can dynamic link to AE and PS, but if my content is out of sync, it's a deal-breaker.
This sort of thing doesn't bother me, since I prefer burning Encore build projects from others applications anyway. And now that Adobe has declared Encore as finished as of CS6, I doubt we will see fixes for any old issues.
Literally the problem addressed above is "feature-length projects, the audio goes out of sync several frames towards the end." For most feature length films, there's no audio and black for a second or more from the end. I don't do feature length films and don't burn with Encore for other reasons, so I can't comment. I am not doubting a problem, but it is not clear to me what the problem is.
Sync issues can be introduced for a variety of reasons, some unrelated to Encore, and others that Encore may play a role in.
Also, I don't see how the burn itself can introduce a sync issue. The image build from Encore, the iso, includes the muxed vobs, so how could it? Encore has frequent burning problems, but how could any burn introduce such an issue.
I've been using Encore for several years and have authored a lot of DVDs at 2 hours or more and never noticed sync issues, nor have I seen it brought up on the forums before, other than user-error situations that were easily resolved. In other words, I don't believe this to be a global issue for all Encore users.
A sure way to have sync issues is to feed Encore a multiplexed file (audio and video together) - you really want them separate with Encore. For instance .m2v and .wav (or .ac3) on the PC, and I think Mac might use .aac? But either way, gotta be separate files.
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