Hi,

Using usb live bt5 for a while, keep getting the io errors on every shutdown. Don't know how to capture the errors while shutting down to paste it here. Anyway, the error messages are all...

You might want to try:
go to the dir which has casper-rw file
type: fsck -f casper-rw

I had similarly problem, and the above fix it for me. Hope it works for you too.