The noise canceling effect is not sufficient.
- Make sure that the noise canceling function is turned on.
- Change to the earbud that allows you to hear the least ambient sounds for both the left and right unit.
- Adjust the headset position to fit your ears.
- The noise canceling function is effective in low frequency ranges such as airplanes, trains, offices, near air-conditioning, and is not as effective for higher frequencies, such as human voices.