Buffer Underrun due to media?

Hello, I’ve an NEC 3540A running the Maddog 1.f2 FW.

I picked up a box of Sony 16x DVD-R (SONY16D1),
and all of a sudden, I’m getting buffer underruns, even at 8x.

Using Nero, I can see the buffer drop from 96-98 down to about 7, and even lower. Also confirmed by the fact the burning light on the drive itself
went out, and there was a light “clonk” sound, which I assume was the drive
trying to resync. (The burns themselves were not lost because of burn proof)

Prior to this I was using a generic 16x dvd+r from office depot and never experienced this problem.

I don’t have any extra media on hand to test with, but I burned a CD at
48x and the meter in Nero never dropped from 98%.

Could this problem be related to the media, or is something else going on?
Thanks for any info -

DMA on?

Well it says it is. According to the device manager,
UDMA 2 is set. I’ve got a second XP install on the same box,
so I tried it there - same problem.

Tonight I wrote a DVD-RW at 4x and the buffer fluctuated between
92 - 98 %. I took a look at some of these burns using the CD speed
becnhmark and quality test. They are OK.

I’m going to try a burn on a different brand of DVD. I’ll update this post
when I get the result.