I've had this thought for a while now, and I think it might be another reality test to add to the toolbox.
Disclaimer: I am still a new lucid dreamer, and don't even have 1 lucid dream under my belt. So I could be spouting complete twaddle.
the test is simple, you pay attention to the sounds around you. These can be subtle like your breathing, heartbeat, leaves rustling etc. Or, they can be sounds that are pretty obvious, or loud. After listening in, proceed to then cover your ears as much as you can, blocking your ability to hear. And, if it works, you should still be able to hear sounds just as well as without covering your ears.
The logic behind this test is the same as the nose pinch test. You are blocking your dream ears, not your real ears. Meaning, sound can still pass through.