I bought some TV shows on Amazon that are produced by a company they own, on demand when you order in DVD-R format. It says in some fine print that it might only play in "play only" devices and that computers will not play them. Well, my two macs with superdrive both spit the disk out within 10 seconds. My standalone DVD recorder and player spits it out too. What are they doing to the disk to make computers refuse to read them? Is there any special software I could download that could override this? The disks seem useless when there are so few players that will evidently, play them. Thank you.