I am 61, about 3 weeks ago I started hearing a human sound, it seems to have somewhat of a rhythm to it, not a pulse, it can be long and then short, short and short, long and steady, that type of thing. I only hear it at home. I went to an ENT Dr. I had a hearing test and they checked my ear drums. They said my hearing is excellent and my ears and nose are clear. The Dr. said he was stumped, after I told him I felt a bit more stress at home and I felt that just maybe that might have something to do with it, he said that's what it could be. Understand, I realize people don't always know that they are stressed, we all respond to stress differently, some may get head aches, or stomach pain, angry, or crying, etc. I have made a point of knowing me, I'd say more than most people know themselves. An example, I once went to the Dr. and told him my symptoms and said I think it's thus and such, after telling me he would do an exam (basically saying he is the doctor and he would tell me what i have) he did the exam and then looked surprised and said, you are right you have this and such. I think the ENT Dr. was guessing and feed off what I said.
My family does not hear this "humming" oh, the ENT asked me to check my pulse and see if the hum has the same "timing" I wanted to tell him he was an idiot. I told him it could not be my heart beat that I was hearing, my heart does not have long beats for long periods and the hum will.
I have looked into this and I have read that it could be a low frequency sound from something in the house that only I can hear BUT it isn't likely that it would be in only one ear.
I only hear it in the house, or in the garage, but never outside, and even when I was in the sound room getting my hearing test I didn't hear it.
I wish I knew the answer, it's got to the point that it will get so loud that I can't think. Even while typing this I have to stop and wait for a few seconds.