I found the URL for that new survey. It's only open for a couple of more hours though.
@nostalgicroxas A frequency difference would make sense to me. When people lose their hearing range, it tends to be lost from the higher frequency end first. Crickets are high pitched little squeakers. Also (and this is a bit of a stretch), direction can change sound frequency like in a doppler effect, so I believe that the noise might pass out of her hearing range when she's nearby or directly facing the source.