I wonder if Gene:
Recorded his queries and played them back to both phones. If not, subtle differences in the voice of the person doing the speaking could alter the results.
Recorded the background noise used in the uncontrolled environment and played the same recording to both phones.
Placed the background noise AND the query in the same recording so each query as heard by the phone had the same exact background noise and spoken query.
Was in a soundproof...