OK, I'm getting coaster after coaster on my NEC 2500A. I'm getting an error of "Invalid Block Address." It's been happening with with several different media. I do get good burns sometimes though. I can get about 2-3 good burns then I start burning coasters. I have tried several different media as noted. I have tried MXLRG02, Prodisc03, MCC (the -r 4x one). They produce the same results. But sometimes, I can get 7-8 good burns straight. It doesn't seem media related. I have also tried more than one burning program, same thing happens. Does anyone know where I can find RecordNow Max 4.5? Oh yeah, the drive is also in a FW enclosure if that makes a difference.

What software versions have you tried?
If you're using Nero 6, make sure you update to the latest version, they are fixing bugs constantly!

Update the drivers for your firmwire card.

You can get the RecordNow trial HERE.

I'm currently on Nero 6.3.1.17 whatever was just released a week or two ago. I've tried DVDdecrypter 3.2.2.0 and 3.2.3.0, as far as my drivers for my fw card, it's built-in to my computer. And I believe it's up-to-date, I just did a complete re-install of XP like a month ago, and I updated everything at the time.

Not by any chance running Nvidia IDE controller drivers are you? Or VIA?
Use only the default MS driver for stability.

Nope, not using either. But doubt that would make a difference, it's on a fw port.

Well then, put it on IDE and see if the problem goes away. You've got some kind of interface issue I think.