The nerves in your ears are overstimulated by the volume of the music, and so you can't hear anything on the phone. Once the music is turned down, you can hear again. That's pretty much the reasoning with needles inserted along a nerve pathway for acupuncture anesthesia. Other points used for this surgery included two on the arm. Their function was to both stimulate additional endorphin release in the body which is an action based on Western medical theory.
Endorphins are one of the body's many pain relief chemicals.
The other point that we used on the arm was Pericardium 6. This point was chosen for its traditional Chinese medicine therapeutic action. This point calms the spirit. This enables the patient to feel calm during the surgery. And this patient was remarkably calm.