Strangely I don't know that either of them interfere with falling asleep. It may very well be that I just don't even try to sleep unless tired and quiet, can't tell--I don't do it consciously. Lately I usually start something on Netflix or YouTube without autoplay so perhaps that's what I accidentally found to work.
This doesn't make sense. If it can be heard by someone else, its by definition an aural stimulus event and not tinnitis.
“Objective tinnitus is a perceived sensation of sound that occurs in the absence of external acoustic stimulation, but it can also be heard by the examiner (eg, by placing a stethoscope over the patient's external auditory canal). Objective tinnitus can occur either from perception of an abnormal somatosound or abnormal perception of a normal somatosound. Objective tinnitus is much less common than subjective tinnitus, but it often has an identifiable cause and may be curable, whereas subjective tinnitus is often idiopathic and is seldom curable.”
The main function of this system is to protect the ear from loud sounds—noise canceling and/or modulate sensitivity as a function of spectrum.