can't delete device

I've been trying to delete a device but it keeps re-appearing after FCS is restarted. The device has many thousand assets on it so when I delete it in the Preference Panel, I can switch to the FCS admin log and see it deleting all the assets from the device. So it looks like its working. When its finally done, the device is gone from the device list, but when the FCS db is restarted, the device reappears. Any clues?

Thanks,

Matt