HELP! problem buring CD's with NEC 2500A

Hey guys!

I have a NEC 2500A that was burning Maxwell audo cd's at 32X just fine till a few days ago. I have the lateast firmware, and Nero 6.6. It burns fine at 24X speed but it fails at 32X with the following error:

11:38:20 PM #60 SCSI -1135 File Cdrdrv.cpp, Line 1445
SCSI Exec, HA 1, TA 0, LUN 0, buffer 0x032A0000
Status: 0x04 (0x01, SCSI_ERR)
HA-Status 0x00 (0x00, OK)
TA-Status 0x02 (0x01, SCSI_TASTATUS_CHKCOND)
Sense Key: 0x03 (KEY_MEDIUM_ERROR)
Sense Code: 0x0C
Sense Qual: 0x00
CDB Data: 0x2A 0x00 0x00 0x02 0xC9 0xEE 0x00 0x00 0x1B 0x00 0x00 0x00
Sense Data: 0x70 0x00 0x03 0x00 0x02 0xC7 0x5B 0x0A
0x00 0x00 0x00 0x00 0x0C 0x00

11:38:20 PM #61 CDR -1135 File Writer.cpp, Line 304
Write error

Can anyone help me figure out what can be wrong? I have tired simulation and it works fine when simulating a burn but when acutally writing it fails.
Not only that but the burning also fails in Roxio 7 and with memorex cd's.

Is this a harware problem or software issue?