I have it to some degree from years of motorcycling, and too much loud music in the earlier years. Not to mention shooting sports, the chain saw and the gas weed whacker (sigh). Yeah, I finally learned about earmuffs and earplugs. At this point it's always there a little bit in the background but most of the time I tune it out. I had a hearing test and found I was missing high frequencies in one ear - the doctor explained that the brain then cranks up the volume so to speak and it creates the high-pitched tone I hear.
I never heard of putting your ears under water - can't see how that would help, unless it's to get rid of earwax? Mine didn't change with sobriety one way or the other, my guess is you have another cause. What I have found is that coffee (caffeine) will definitely make it worse. Perhaps you are drinking more coffee now in sobriety? Also if your blood pressure is up it can make the ringing worse - my ears are ringing a bit right now after a hard bike ride earlier. Most of the time it fades into the background for me but I'm very protective of my hearing now so it doesn't get worse. I use earplugs for all sorts of activities and order them by the hundred pack.