One thing I've done is changed audis. I've changed them several times over the past several years because I was so frustrated with the feedback issue, and having constantly sore ears from poorly made earmolds (they made my ears bleed!). And none of them seemed to take me seriously. I found a new audi, based off a referral from a friend, and boy, do I ever love her. My first visit with her, she made me new molds and they are a dream. It's now time to replace them, but that's only because of age. So that really seems to make a difference with feedback. At least for me.