The red alert didn't alarm him. The big man just returned to his room, trading the standard shotgun for what Cable had affectionately deemed the 'fuck you o'matic'. An extra long clip for it was shoved into a pocket, and off he went. Would have been nice if he'd had time for armor, but without knowing what was going on he wasn't going to take the time.
The big man hit his communicator, requesting a location for the intruder, and once he had it, off he'd go. One person walking it. Either they were stupid powerful, or just stupid. Or not a threat, but that wasn't even on his radar at the moment.
Rather than confront the man head-on, the soldier would circle around through the woods. Coming up a bit behind Audio, gun leveled. "Hands up, on your knees. Refusal to comply will result in your guts being splattered across the yard." Just in case the guy had any doubts as to the consequences of his actions.