My Twitch shuts off when Itch starts. Itch displays a flashing "hardware disconnected" error. It then goes to a screen that says that the "firmware update" has failed. It gives the error code of "-1." It asks if I want to try again. When I click yes, it shows a status bar for a split second and then goes back to the error message.

I've read through these help discussion pages and tried everything I've seen suggested and every possible way of doing the installation in a different order, etc...

The Twitch appears in my device manager with with most recent Novation driver number and says it's working.

If I attach the Twitch and open FLStudio, it functions fine as a midi controller.

The problem appears to be just with Itch.