Booting from the disc revealed it was unrecognised so I burned another - same issue. Burning the same .ISO from a different computer worked so I was sure there wasn’t an issue with the image. I began to suspect a faulty DVDRW drive but even after swapping it any CDs burned remained unrecognisable, even to the drive they were burned in. I tried one of the laptops that came preinstalled with the Dell Windows XP configuration and sure enough it was bootable. I then assumed there was an issue with a driver or some software on the laptop that was preventing the laptop from burning the CD successfully. A peek in device manager revealed no issues with the DVDRW device (mine was a TSSTcorp DVD+-RW TS-U633A). I checked both Dell and Intel’s websites for newer drivers but I already had the latest.

The only application I didn’t have installed was the Intel Matrix Storage Manager, a program used to monitor disks/drives and report their status and/or RAID condition. It seemed pretty far fetched but as the DVDRW drives were SATA300 I decided to install the application. After installing it and burning yet another Knoppix CD I was astounded to see that when I put it into another computer I could successfully boot from it! After testing this on another of the laptops I was sure that it was the lack of the Intel Matrix Storage Manager that was causing the CD burn to fail each time. One thing I only noticed afterwards, when initially using MagicISO to burn the .ISO image (pre the installation of the Intel Matrix Storage Manager) the application never reported it was attempting to 'Close the Session'. Since installing the Intel Matrix Storage Manager I have not had any further issues burning audio or data to CD or DVD.

The latest Intel Matrix Storage Manager is available direct from Intel - Here

A quick dig around on Google afterwards revealed similar issues for Dell owners of Latitude E6400 and E6500 series laptops. It now seems this issue is commonly found on most laptops with the same SATA DVDRW drive as above.