Many people have this. It’s “hearing” a sound that isn’t really there, but the person experiencing it isn’t crazy and knows it’s not really there. It can be a tone, or rushing sound, or… something else. In the last few years, when I was getting treatments attempting to reverse some hearing loss, I noticed I have it in a very, very mild (and of course, screwy) form.
If it is very quiet, I can hear tones. At least two, maybe three, alternating or at least taking turns as it were. I felt my pulse to see if there was any relation and as far as I could tell there was not. The tones sort of remind me of Frequency Shift Keying. They are slow enough to recognize they are individual tones, but too fast to readily write down or such and too simple to convey information of any significance – as if they did, would, or could. But since I am seldom anywhere really quiet, the tones don’t really bother me.
Since hearing was involved, in that time I had a few hearing tests. Low tones, high tone, low volume, downright faint, and so on. Also ‘repeat the word back to me’ which was new to me, but it had been many, many years since the last hearing test.
And this brings me to a quirk of sorts. I do not know if this is normal and a thing of common experience, or if it is unusual and few experience it. For a long time, going back into the 1970’s at least, every once in a while I would “hear” a tone kind of like in a hearing test, except this was just at random. It is usually of high pitch, is usually of “normal” or slightly less volume – it’s not overly loud, doesn’t interfere with normal conversation, but is more than enough to be noticed. Any given tone is constant in volume and pitch. The tones are varied in pitch, and duration. Some last maybe a second or a few. Others can last perhaps as long as 20 or 30 seconds. Occasionally one tone will be followed, after a slight break, by another. This is rare, but it happens. Then, the tones themselves are infrequent. The tones, when they happen, seem to be in or from one ear only. I have not found anything that seems to trigger these events, nor simply increase their probability.