About burning DVD's

Try some DVD-R media, and see how well that works for your hardware. Also try a different DVD+R formulation.

When things go weird, always try the slowest recording speed the drive and the software will allow, and work your way faster from that.

I spent a lot of time with writing recording software for optical devices, and I'm still surprised that CD and DVD works at all, much less as well as the optical stuff does work. Saw all sorts of wacky errors returned back from various drives, and from the blank media. Also saw some of the sorts of creeping crud — degraded recording substrates — that occurred on various media over time.

There are different types of DVD media — DVD+R, DVD+RW, DVD-R, DVD-RW, and DVD-RAM — and different drives support different combinations. Recent DVD-capable drives usually support at least the first four DVD formats if not all five, as well as CD-R, CD-RW, and some of the double-layer DVD DL variants. Every DVD drive I've met can read CD-ROM and DVD-ROM; the prerecorded media formats.

In addition to the CD-ROM and DVD-ROM formats, I'd tend to expect the following with a typical cheese-grater Mac Pro: CD-R, CD-RW, DVD-R, DVD+R, DVD-RW, DVD+RW, DVD-R DL, DVD+R DL. You can get the formats supported from  > About this Mac... on recent versions.

With a cheese-grater Mac Pro, your external choices are external SATA if you want to add a controller, or add and configure some other hardware options, or FireWire 800 or FireWire 400 if you can find a recording drive that still supports that, or USB 2.0 — which is comparatively slow.

Apologies. I do not know what is obvious and known to you, nor what is not known or not obvious.

Try some different media combinations, and slower speeds, and see whether you can get that to work. See if an optical drive cleaning disk helps.

You can certainly choose USB 3.0 for your recording device, but the cheese-grater Mac Pro does not have USB 3.0 support in the standard configuration. Which means reading and writing will run at USB 2.0 speeds. Which is slow.

You could potentially also acquire a second optical drive for the second internal bay on the cheese-grater Mac Pro. OWC offers such packages.

As for your core question, I do not know what's wrong with your burner, other than that it does not work reliably. It may not work because the media is not compatible, or that the batch is flaky or stale. The drive may not work because there's a hardware problem, or that it's old or just dusty, or it may simply be because all optical drives have a longstanding habit of getting flaky or failing. It's also possible that the drive can lock itself into a different playback region — if used with commercially-produced recorded DVD media, though that doesn't usually effect recording.

Apple has removed optical drives from newer systems. That they were swapping the drives for folks is probably a factor in the decision — Apple has replaced the internal drives on most of the local MacBook Pro laptops that have had optical bays, with those optical drives lightly used, and that was in the first three years for each of laptops.

Again, optical drives are comparatively unreliable, and the recordable media can range from functional to unreliable to defective. There are reports about a NIST / Library of Congress study that found some DVD recordable media would be readable for less than two years, once recorded. That was from some years ago, and substrates and dyes have likely changed. What that has done for longevity now, who knows?

As for the recording media, I've had expensive, brand-name media that was utter junk. I've used some media that worked reliably, and where the next batch from the same source and the same vendor was junk.

The burn folder has been around for a number of releases. Snow Leopard had support.

From reading these posts, is appears that the computer you have and the internal CD/DVD drive (burner) you have are more than adequate for what you are trying to do. There is no need for an external CD/DVD drive unless you want to do lots of replication. The built in disc burning function is less than desirable so you need to be looking at your disc burning software. Your previous experience with Toast Titanium and OS 10.6 SL, is the only proof you need. If you want to be serious about making good quality master CD's and DVD's, you need to keep updating and progressing. Stick with OS 10.8.5 and buy a new version of Toast and solve all your problems.

DVD - (minus) R discs have proven to be the most reliable media for me. 99.99%.

Now for my two cents worth:

I get sick of seeing posts from people who complain about the cost of upgrading software. If you own a Mac, get real, love your mac and be proud of the innovative software because it's the best computer system you will ever own.

David.