[dnanian]

OK. I don't know if you're downloading/bittorrenting/etc something overnight, but what you'll want to do is open Terminal. Then, copy the following to the clipboard:

sudo lsof | grep SDCopy

Paste that into Terminal. Press Return at the end of the line, then enter your password (it won't echo) and press Return.

That'll print a list of what we're copying at the time -- the last two lines are what we're reading and writing. That should be the file that's causing things to get stuck, probably because it's being written while we're trying to back it up.