Liteon DVDRW SOHW-1633S (Won't Copy CDs)

I’ve installed a Liteon DVDRW SOHW 1633S, but after I copied one Music CD to Music CD with no problems it will not copy a CD either from files on the Hard Drive or from another CD in the CD ROM. I get a message saying Buffer Underrun Protection Activated and the CD I am trying to record onto is ejected from the DVDRW. I am using Nero Software but their technical support has only sent me auto replies to acknowledge receipt of my problem, but no suggested solutions. I know very little about computers so this may be a very simple problem, but because of that I haven’t even got as far as burning anything else. I have a 902MHZ Processor, 320MB of RAM, a new 40GB HDD, and Windows XP Professional Version 2002. Has anyone else experienced this problem and if so can someone help me solve it? Thanks, Dave.