How come I can only export a limited about of Sony XDCam clips at any time?
 

I'm using FCP 6 to export movie files and burn them onto a XDCam disc. I'm exporting them one by one (I cant figure out a way to do a batch for Sony XDCam export but that's another question...) and after doing a bunch, I'll get the error message "Export Failed Final Cut Pro: Error Writing to File." If I wait a bit and the exporter list gets smaller, I can try again and export succesfully. I cant figure this out. It's almost as if the exporter list can't get too large, but that seems odd.

Anyone have an explanation for this behavior?