That's interesting. I experienced the opposite with my iPhone and AT2020 microphone. Ultrasonic always worked perfectly, audible complained of packet loss.
I am not sure what the noise floor looks like when comparing ultrasound to the normal audible range. It does seem unlikely to me that all this street noise would only be in the audible range and not ultrasonic, but since my ears can't hear ultrasound, I have no idea. Ultrasound did work better.
I tried the image as well; no idea if it worked. I got tired of waiting.
