Unable to flash tx1 with jetpack 4.4

I am having problems flashing a TX1 card using the jetpack 4.4.
The flashing stage (seems to) starts normally, slows down towards the end and then stay stuck at 99.9% (I stopped it after more than 2 hours).

The TX1 card is correctly configured in recovery mode and connected to the host machine (the TX1 disk is briefly mounted at the start of the process).

The host machine is an Ubuntu 16.04 in a Virtual Box.

Thanks for your help

VMs are not supported. It doesn’t mean you can’t make a VM work, but USB is disconnecting and reconnecting during a flash, and the VM tends to not reconnect correctly. You will have to work on your VM configuration so the Jetson is passed through from host to guest regardless of how much disconnect/reconnect occurs. Having dual boot will probably be less frustrating (versus a VM).

Either as a VM or native Ubuntu (dual boot perhaps) you would probably be better off with Ubuntu 18.04 instead of 16.04 for these more recent releases.