I was having thepod x3 live stuck on update flash problem. Finally, finally got it resolved today. This worked for me:
1) Try and use the USB ports located on the back of your computer if possible. i.e. one that is soldered to your motherboard.
2) Use the version 1.0 firmware.
Note: step one was suggested by Line6Don. Thank you!
Also, after I got the pedal working w/ version 1.0 firmware, I tried updating to the newest firmware and the problem came back.
I went back to version 1.0 and the pedal is working again! Thank goodness...
Good luck y'all.