Barking up the wrong tree here.
Your problem is the combination of the media and your player. Lower your burn speed, and if that doesn't work, try different media.
In any case, I assure you that the 451 is not burning at 8x unless you futzed with the firmware. But you can set Nero to show the actual burn speed if you want, or use CDSpeed with a blank disc to run a transfer rate test or data disc test.