AFAIK when there is not enough external sound input, the brain amplifies the signals from the inner ear in an attempt to compensate which leads to hyperactivity

AFAIK when there is not enough external sound input, the brain amplifies the signals from the inner ear in an attempt to compensate which leads to hyperactivity in the auditory nerve and auditory cortex, which can be perceived as tinnitus. So you cannot cancel a 'signal' that doesn't exist. This is my understanding and I may be wrong.