If you ruin your hearing, and get serious tinnitus, nobody on Earth can help you. Never have the volume up for some form of sensuous reward.
Yes, you can have some tinnitus and a class 1 medical, but it's all a question of degree. High tone deafness is endemic in aircrew that flew the older stuff.
Some antibiotics are thought to cause tinnitus. Tetracycline I believe is one, but you need to research this.