I'm using DVD Studio Pro 4 to produce HD DVDs using standard red ray DVD-R technology. I know it is supposed to work, but I'm still having issues: if I encode with H264, the video plays back in slow motion. If I use MPEG2, it works fine but can only fit 30 minutes onto a disk. And no matter what I do, I can't get audio to work, either in AIFF or AC-3. I'm playing the finished DVDs off a Toshiba HD A2. Can anyone help me by telling me what settings you're using?