Beware of noise canceling headphones if you have tinnitus! I've had tinnitus since 2006, but over the years my brain had pretty much blocked it out 90 percent of the time or more. I felt very fortunate. Then this weekend, I attended a meditation course. During the class, I didn't notice the tinnitus during the practice meditation in the quiet room. But after I got home, I put on noise canceling headphones to help with exterior noise during my home meditation practice. I had never used them before and immediately noticed kind of a high pitch and almost a vacuum feeling in my ears. And then I almost immediately became aware of the tinnitus. I wasn't concerned because I knew I would sometimes hear it at night or in other quiet moments. I wore the headphones about half an hour, during which time the tinnitus made the meditation pretty difficult. But then after I took the earphones off, the tinnitus didn't go away. In fact, it was louder than ever. That was 4 days ago and there's been no change. I am having more trouble sleeping than ever before. I'm having to run an air filter machine for the droning background noise. Now, I have noticed that sometimes after concerts, during which I wear earplugs, my tinnitus gets a little louder, but it is always back to normal by the next morning. This is different and I'm very concerned.