I bought 2,0 off of the US store about two hours ago and it began downloading. When I try to upgrade my device (from clean 1,1,4), it goes through the extracting software stage and preparing iPod for restore stage. Before it gets any further, I get "Unknown error (1604)" and it fails. I've tried putting it into DFU mode and that didn't do anything, and I can't seem to kick it out of this inoperable state. I'm on iTunes 7,7. Any ideas as to why this isn't working/how to fix it?