When I have my noise cancelling turned on, the right cup makes a tapping noise constantly, almost like the sound of a helicopter. I've had these since December and today is the first day they have started doing this. I'm use to the static which occurs when noise cancelling is on and no music is playing and I'm not sure if that is normal either, but I have grown accustomed to it. However, this tapping noise is almost maddening. I've tried resetting the headphones to factory settings and that did not help. It still occurs anytime the noise cancellation is turned on. Any help would be appreciated!