Why are all the buttons grey on the MTM400 remote user interface?

Why are all the buttons grey on the MTM400 remote user interface?

If you have a firewall installed on your computer or otherwise between your computer and the MTM400 this may prevent the MTM400 from sending certain data back to your PC which will result in all the buttons turning grey. Try disabling the firewall between you and the MTM400 and see if this resolves the situation.