I too have what i believe to be permanent ringing in my ears, i never had it until i got off the gabapentin, i am 100% sure now that is what caused it, i thought it was only me or my old age catching up to me but now you and a few other people mentioned the ringing after gabapentin use, i am postive it is from that.
It started out as a very mild slight ringing noise about a week into W/D, after about 2 weeks and still dealing with the menal part of the W/D i was outside smoking a cig and i felt the pressure in my head change and my ears started ringing louder, praying it would go away but it didn't, flash foward over a year later i still have it, but i am use to it now, although some days it is loud and annoying, i tolerate it, i do need some noise around me 24/7 or it is kind of loud when it is quiet in the room.
Gabapentin legit fucked my life up, biggest mistake of my life, that is why i ask people to post there W/D and months following so i can get input and share stories on the situation, ever since i stopped taking gabapentin i feel like a total different person and it scares me sometimes and i would give my left nut to go back to how i use to be before hand.
I suffered from pretty bad derealization for the first 6 months after stopping, could barely even leave the house or drive when i did leave, i constantly felt like i was gonna pass out and die which sent me to the ER multiple times, i had ringing in the ears and still do, heart palpations, blurry vision, hot and cold flashes, no motivation, would shake and get jittery sometimes and then little things, i would blank out when thinking, boredom and loss of sleep etc etc...
Some people get lucky and avoid all negative effects, me and around half the people on this thread were not so lucky, it don't seem like it is causing you harm until you quit the shit and then you find out the hard way.
And the fucked up part is doctors don't even know about the negative effects, it is a severly under researched drug, they push it on people and more times than not it causes more harm than good in the long run, my advice is to never touch it, if you do then take it for life do not ever come off, if you want to stop do a extremely long taper.