I'd strongly encourage listeners here to heed this advice. After about 5 years of listening to hp's at what I considered a very modest or medium level, I know have developed tinnitus/ringing in the ears. It's constant permanent and incurable. I have no hearing loss as of yet. But this is a real problem that I feel needs more attention.
This. Tinnitus is such a maddening ailment, although years of drumming and concert-going are more the culprit in my case. I find headphones provide a nice distraction, but I continually have to be wary of volume. Protect your hearing folks!