First, I was using official Apple DVD-R media (10 pack), and I only got 2 error-free burns out of that. Then I bought a (much cheaper) 25-pack of STI DVD-Rs, and I got 17 good discs out of that (and even at 68% success rate, they were cheaper than Apple's media.)
So, that's 19 DVDs, 16 coasters, and I seemed to have the process down. I was getting about one disc written a day.
Then I bought a 50-pack of STI discs, from the same store, since those worked ok last time. And now, I can only rarely get it to write the disc to completion: what happens is, iDVD spends about an hour "encoding assets", then ejects the disc. The progress bar says "46 minutes left" forevermore, and I have to force-quit iDVD. Syslog says:
- iDVD: Burning to MATSHITA DVD-R UJ-815 D0C4 via ATAPI.
iDVD: Requested burn speed was max, actual burn speed is 7x.
iDVD: Burn started, Thu Mar 6 11:37:44 2003
iDVD: Burn underrun protection is supported, and enabled.
iDVD: Write (10), block: 0, count: 32 -> 3/73/03 Medium Error, Power calibration area error
iDVD: Burn failed, Thu Mar 6 11:37:56 2003
iDVD: Burn sense: 3/73/03 Medium Error, Power calibration area error
iDVD: Burn error: 0x80020022 The device failed to respond properly, unable to recover or retry.
Some Googling reveals that the "power calibration area" is a spot on the disc that the burners do some initial read-write tests to, to figure out how much cooking the disc needs or something. So that error message means, "bad media, or maybe upgrade your firmware, or maybe it's an iDVD bug. Did you try rebooting?"
At this point, I've gotten that error on 26 discs from the new pack. It wrote 4 discs to completion (without the power calibration error), but those discs don't play right (the last few tracks are unreadable.)
I also tried all the usual suspects: check firmware version; upgrade to latest OS release; regenerate the iDVD project from iMovie after deleting a few frames; reboot; power down and let the drive cool off overnight; bleed a chicken; etc.
Lacking any other ideas, I guess I'll just keep trying until I run out the rest of this 50-pack on the off chance that there's one good disc in there. So far these DVD-Rs are costing me around $7 each, I think, and take an average of 2.5 days to burn. That's a hit rate of around 28%. Color me unimpressed.