Psychosomatic doesn't quite mean that. The symptoms are real and physical, but the origination is in the mind somehow, maybe through stress or a learned behavior. Solve the stress or mental conflict -> seemingly unrelated symptoms stop.
I think in practice it's basically helping you come to accepting you have tinnitus because they can't do shit all about it, or understand why it happens in a bunch of cases.
There's a neural theory of tinnitus, that says you hear it because your brain is compensating for lack of signal at some frequencies.
Like the amplifiers are turned up to max at some frequencies, and the neural net maybe even adds an interpolated perception.
If that theory has anything to it, it makes sense that it might be possible to train your brain to reduce the effect.
That's not just "accepting", but it might be difficult to perceive a difference if "accepting" results in "not noticing as much", and "not noticing as much" is indistinguishable from "turning down my brain's perception gain for these signals".
I can tell you first hand that while you can indeed become somewhat... used to that constant ringing sound (1), it isn't exactly "tuning out" like with typical environmental noise (street sounds, wind or rain).
Here's what it's like.
Imagine someone is standing right behind you with a little whiteboard and scratches the chalk on it. It makes this high pitched sound you cringe at, right?.
Someone is doing that slowly, and the chalk is tiny, so the sound is not super loud, and can be covered by music, people talking etc.
But that person keeps scratching all the time. A little bit. Every second of every minute, of every quiet moment at home, in the mountains, in your electric supposedly-quiet car, of your every mindfulness meditation practice. For years.
So can you "tune out"? Maybe if you dull your senses and have laser focused attention for most of the day. But it keeps coming back. And again, and again. It can be confusing, annoying, funny, or just be there. Your reactions vary, as you learn to adjust to it (if you try to).
But "tune out" suggests once it's done, it's gone.
This is never gone, it's the opposite of gone - it's there even if I stop breathing!
(1) Actual nature of the sound varies between people.
I find I "tune out" because I'm concentrating on something else.
Same way I stop noticing sometimes that someone is trying to talk to me, or that I have a deadline that's drifting past, or that I haven't eaten or moved from my chair all day.
The sound doesn't go away, but I stop noticing.
I'll start noticing again if I'm trying to listen to something quiet, and realise the tinnitus is louder and slightly masking what I'm trying to hear.
Or any time I pay attention to what I can hear in the background.
I don't tend to notice the tinnitus if music is playing, or I'm talking with someone.
I agree with you that it's never gone. Though I've noticed the volume varies a lot. From quiet like the background sounds from outside where I live on a quiet day, or even quieter than the sound of breathing and my heart beating, to as loud as someone talking to me. The tones vary too. Fortunately they are usually higher frequency than what I'm listening too which reduces masking.
I've had tinnitus since I was a child, so I doubt it's due to age-related hearing loss. I don't know a cause, but back then I noticed it was louder when I was ill and stuck in bed, and actually I found it comforting then, like it sounded like my body processing as it should.
