External DVD burner wont mount blank media.

[AuroraProject]

I picked up a Lite On DX-8A1H external slim type dvd burner for use with my MBP. If I put an audio cd or dvd movie in it works fine, iTunes or DVD Player open and everything is great. However, if I put blank media (cd or dvd) in it does nothing. System Profiler sees the drive, but the media doesn't mount to the desktop. I can burn to the blank media using Toast, but it's like the blank discs are invisible to the OS. Any ideas as to why this happens?

17" MBP, 2.16ghz Core Duo, running 10.5.2

Thanks.