No, everything seems to be fine until I play the DVD on my DVD player. I checked how everything looks in the VLC player, and all indications at that point are spot on. The sound is fine on the riff and the movie, and I made sure to get the NTSC version. I was worried on one of my earlier ones that I might have not changed the setting to NTSC from PAL when I reauthored in ReJig, but if that had happened, wouldn't the entire movie be too fast, not just the audio? (And it's both the Rifftrax and the movie audio together that are too fast.)
And in fact, I can even play the finished DVD on my computer and it's fine. I would say it could be a problem with compatibility, but the New Moon Rifftrax is perfect, and I've recorded other things with these DVDs that have worked fine on this player.
Thanks again for the assist!