This old, but useful thread was bumped today. I have been wondering about this myself as living in Japan, it can be troublesome buying headphones as many people here smoke. Shotgun summary of the advice given: Hydrogen peroxide and ozone will fix the problem.
I was recently given a pair of AKG 340s in perfect condition except for the fact that they've been sitting around for a couple decades in a small apt with 2 chain smokers and their chain smoking friends. My ears love them, but I can't stand the smell. Any ideas?
An ex-chain smoker