alt Hacker NewsMy XM4's always do that at the beeps from the cash register, although I always attributed that to their volume rather than frequency. My theory was that they refuse to produce sound loud enough to cancel the beeps for safety reasons.
My XM4's always do that at the beeps from the cash register, although I always attributed that to their volume rather than frequency. My theory was that they refuse to produce sound loud enough to cancel the beeps for safety reasons.
I suspect as much too. If there's a failure to match the noise perfectly then the headphones are just going be be blasting a loud sound into your ears. And if it matches the frequency correctly but lines up with the sound instead of being out of phase, then it's acting as an amplifier!