Invalid Block Address Error with Nero = Many Coasters

Hi,

I've been able to somewhat making backup copies of my son's anime
DVD's with my Khypermedia Combo 8X DVD+RW / 24X CD-RW drive for a
while. The drive was brand new when I purchased it and I've had it for
about 2 months. I don't do the backup very often. So far I've made
about 11 backups.

Since about 3-4 days ago I've been making nothing but coasters. I use
DVDShrink along with Nero 6.3.0.3 which came with the drive. Sometimes
the burn process would to go about 2% and failed with the "Invalid
Block Address" message. Sometimes it would get up to about 50% then
failed. I used no name blank DVD disks which worked fine before, but I
was able to burn at 4X only. I've never been able to burn at 8X, ever.

I run Windows 2000 with 40 GB HD drive, 2 partitions of 20 GB each. I
have 128 RAM. Any ideas why this error started recently? Is the drive
failing or do I need to reinstall the software or what?

I'd greatly appreciate any suggestions.

Thank you!

Lucky Dog