首楞嚴義疏注經 3.192

3.192

初句不聞無界破。若不聞識亦不聞聲，能聞所聞俱無界義。後一句聞識同聲破，可知。

The first sentence refutes it on the ground that if it is not heard, there is no realm: if one does not hear consciousness, one also does not hear sound, and both that which hears and that which is heard lack the meaning of a realm. The latter sentence refutes it on the ground that hearing consciousness makes it identical to sound, which is clear.