Problems with "Boot from CD" option in BIOS

[MrMilney]

I've been having an annoying little problem with my system since I built it. I have an Epox 8K3A with the latest BIOS (6.00PG), a Toshiba DVD drive (SD-M1612) as the primary slave and a Plextor PlexWriter 24/10/40A as secondary master. When I set the boot order in BIOS to boot from CD before the hard drive one of two things happen. If there is a CD in either drive it behaves as I would expect (gives me the option to boot from it or not). If there is no CD in either drive then the system hangs when it tries to boot from the second (Plextor) CD drive. Does anyone have a fix for this? I've tried Google, searched here and read through the FAQs but didn't see the anser I need. Any help would be great.

Thanks!