You may use the AV50 for strictly noise cancelling by using the audio cable provided, a Bluetooth connection to a device or contacting ZVOX for a 3.5 mm snub plug which plugs into the headphone jack for the ability of constant NOISE CANCELLING.
Reason: By establishing one of these 3 connections, shuts down the "Auto standby/Pairing Mode". If you DO NOT, the AV50 was designed with a type of "Auto Standby sensor/Pairing Mode" that shuts OFF the headphones after 10 minutes of an unsuccessful Bluetooth pair/idle mode.
If you want to use the headphones in an airplane or at an event with strictly Noise Cancelling you must apply 1 of the 3 options above.
If you have any questions please call 866-367-9869.