Ixpand firm wear update fails

Ixpand firm wear 4.4.1 try to install and failed, I plug in the ixpand and it then asks to do the firm wear update, I say yes and the update starts it runs until the iPhones battery or the ixpand battery goes flat.
Can anyone help.

what host and iOS version are you using? Do you have access to any other compatible iOS device you can try the update from? If it fails there as well could be a hardware problem so you may want to contact sandisk support and see about warranty replacement.