So, my basic understanding is this:
A neuron can either send a signal, or not. Sending a signal costs energy & work (and the neuron might only survive so and so many send-cycles).
So let's say the output of a neuron tells you whether a state is assumed, or not.
To keep the neuron alive and energy consumption low, if the state being assumed is the rarer occasion, then the neuron sends a signal if the state is being assumed, and vice versa.
I'd now guess that hearing a sound (or more low level, a sound wave being of a certain frequency being in the air), is more unlikely than the converse.
So for a person with a Tinnitus that produces a constant sound, somewhere in the brain/the receptory neurons for hearing, we should have one/a few neurons that fire permanently.
We should know rather broadly where the information processing for sounds happens, and neurons that always send should be anomalies (as a neuron that always sends doesn't transmit any information at all).
So why can't we just scan for neurons in those regions permanently firing, and then destroy them?