Proper fit on your head is important both for comfort and optimal noise-reduction performance. Here are a few guidelines:
Wearing the headset properly
Use the left (L) and right (R) markings above the earcups to orient the headset properly
As you put the headset on, lightly grasp each earcup and adjust it so its cushion is completely over your ear. You should feel an even, gentle pressure all around each ear
Adjust the headband so it rests gently on top of your head
Make your final adjustments with the headset powered on in a noisy environment. In very loud conditions, such as during takeoff, you may experience a brief reduction in noise cancelation as the headset compensates for a momentary pressure change.
Conditions related to fit
A low, rumbling sound or frequent, brief losses of noise reduction may indicate an improper fit or blocked earcup ports. During a long flight, you may feel a slight pressure point, which can be relieved by adjusting the headband position. Your experience with using the headset will help establish a sense of how it should sound and feel.
Microphone placement is important for clear communications. With the headset on your head, make these adjustments:
Grasp the boom with your fingers and move the microphone up or down so it is level with your mouth
Pull the microphone in toward your lips. Position the microphone with its talk side facing in. Though it will be slightly off center, the microphone should be ½-inch from the opening of your lips
Make sure the talk side of the microphone is facing your lips. Do not purse your lips
The control module cable is fitted with two clothing clips. Use the clips to attach the headset cable to your clothing, a safety harness or an aircraft door pocket