MacBook Pro freezes when MyBook Studio is connected

Greetings,  I connect a 1TB My Book Studio external HD to my Apple MacBook Pro to store video files, etc…   When the HD is connected my laptop will freeze up and the only way to get it to unfreeze is to unplug the firewire 800 cable.  

Has anyone else experienced this?  Does anyone have a suggestion?

Thanks in advance, Scott