I had 7 other people try it on my system. Nothing worked. I had to give commands by holding the right trigger and going through everything with the D-Pad.
That sucks. To be honest I only used the voice commands during the "Activation" phase and all those worked perfectly. Probably because it already had predetermined commands that it wanted you to say so it already knew what to detect. Are you actually enjoying the game? From the one match I played, the game just didn't seem any fun at all. Sure, it has actual strategy and concepts behind it, but it just comes off as flat and boring.
Send your infantry to go-points on the map to capture locations. Keep the enemy from stealing the location from you. Upgrade your locations to use special map attacks against the enemy. Constantly spam reinforcement deployments and rush them to your captured points. Boring.
World in Conflict is a much better version of this game.