Hi, I'm still new to all this, but I've tried to do my research before asking. I had some success with burning regular DVD-Rs, so I thought I'd try my hand at burning a DL disc with my DL external burner. I wanted to back up my Science of Sleep DVD, so I ripped (MTR) and burned (Toast 7 Titanium) as DVD-ROM UDF, all as normal. The finished disc played in the external burner just fine, even using the Apple DVD player that comes with the comp. BUT when I try to play the DVD in the computer itself, the disc just automatically ejects. The disc doesn't play in normal DVD players either. Can anyone help? Thanks so much!