Just run the Hearing Test on YouTube and I lost the sound around indicated age of 71 on the gauge - not bad as I'm 78, 16350 hours over aproximately 37 years of flying, including over 8000 hours on Bell machines, 205, 214B, 206 & 212, plus 6500 on the S61N (North Sea & Falklands) then a handful of hours, 650-ish, on the 332L1, not to mention the Sioux and Gazelle.
My high tone hearing is suffering a little though, but I am informed that that is due to normal age related loss.
its a bitch getting old, but I'm still here to complain about it !!😉😉👍👍