They may want to disable that feature occasionally.
I sometimes wear glasses which prevent the headphones from forming a perfect seal. If I walk around with the headphones on, I get a "wow" going on which is quite tiring. Turn the NC off and they're ok. I only rarely do this, so I wouldn't have bought a dedicated pair only for this purpose.
I sometimes wear glasses which prevent the headphones from forming a perfect seal. If I walk around with the headphones on, I get a "wow" going on which is quite tiring. Turn the NC off and they're ok. I only rarely do this, so I wouldn't have bought a dedicated pair only for this purpose.