But Fox said the revelation had no impact on the players.
Image slideshow: Best pics All Blacks v Wallabies
"It was touched on really briefly at a walk through and that was it," said the former All Blacks Superboot. "I can cast iron guarantee and assure everyone that it had nothing to do with our motivation whatsoever.
"It's not the sort of emotional driver that works for us. They were made aware of it because they spent time in the hotel room. Before that they had no knowledge whatsoever. It was touched upon for about 10 seconds at most, flushed, get on with the job. "
Asked how players reacted, Fox said:
"(There was) No reaction. We were just about to do a walk through, so they didn't have time to process it....just get on with the job."
Fox was at pains to point out the All Blacks were not accusing anybody of planting the listening device.
"All we've said is we found a listening device in one of our rooms. We're not accusing anybody of putting it there. The media can speculate all they like but we don't have any proof on where it came from. All we know is the facts. We found one and it's now in the hands of the police. It's as simple as that."
Fox confirmed the bug was picked up in a routine security check carried out by a security firm contracted by the All Blacks.