When I was listening and I heard birds chirping my mind would say "I hear birds chirping..." and when I heard the water rippling, my mind would say "I hear the sound of water rippling..." and then I would think "but I'm not supposed to recognize the sound as being water or the sound of the birds chirping as being birds chirping..." and then I would think "I'm not supposed to be thinking that I'm not supposed to be thinking about what the sound is..." and so I sort of fell into this ever-recursive, spiraling loop of meditative frustration. Also, this technique relies upon a person's ability to hear. It would do no good for a deaf person.

Nick: It's not about supposing to do anything. If you hear a bird, let the sound enter your being, hear it for what it is, hear the chirping, feel the cooling breeze and the hard surface on where you sit. Feel your in breath, fully, feel as your chest expands, and then, as it deflates, letting the breath go. Being fully in the moment, with no other plans, or judgments on what's happening; that's meditating.

I find that my mind tries very hard to cast the sounds as an object in a 3D space. This will be a big challenge for me to overcome. There are obviously ways to 'cheat' to get this effect :)

I studied kung fu with a chinese kung fu master who taught a breath and stretching technique called 'ta mo chi kung' attributed to Bodhidharma, and at a certain point, one is instructed to look down your nose and touch your heart, listen to the all the sounds of the world. It only done for a moment, and my impression is that for most to go longer than that creates an over-effort, trying much too hard. Its as if one can only capture a moment at a time of the state of mind at first.