Hi there I have been trying to author video's using both DVD Studio Pro and iDVD but the DVDs are not burning. I am not doing anything different to how I used to but at the last minute the DVD is ejected and there is an error report "the recording device reported the media error. Unknown device error". I have tried various burns using a variety of formats - .mov, mpeg 4 but nothing seems to make a difference.
I have a Mac Book Pro and its using Mac OS x Version 10.6.8
It plays DVDs perfectly so I don't think its a hardware problem.
This is certainly difficult to diagnose online! However, I would encourage you to Build your disc in DVDSP (using the Build command), which creates an AUDIO_TS folder and a VIDEO_TS folder on your hard drive. Then use Toast or other software to burn those two folders onto your DVD. That way, you are using each program for its strengths—DVDSP for authoring, and Toast for burning. By splitting the task into stages, you make troubleshooting easier.
Within Toast, you can know if you're using discs which your drive can actually burn. This really isn't much of an issue anymore, but it is something to "check off".
Also, by building before you burn, you can emulate the disc by using Apple's DVD Player to Open the VIDEO_TS folder, which allows you to play the disc as if it was burned. Once you've tested it thoroughly and know you want to burn it, you then use Toast to do so.
Another possibility is that your drive is no longer working properly. I've had a drive stop being able to burn; I believe it could still play discs, but I can't recall. You can run Hardware Test, perhaps (depends on model) ( http://support.apple.com/kb/HT1509?viewlocale=en_US&locale=en_US ) or you can take your MacBook Pro to the shop and have them take a look at the drive.