User Manual - Page 81

Depending on the ambient condition and the type/volume of audio playback, the ambient sound may not be heard even when

using the Ambient Sound Mode. Do not use the headset in places where it would be dangerous if you are unable to hear ambient

sounds such as on a road with car and bicycle traffic.

If the headset is not worn properly, the Ambient Sound Mode may not work correctly. Wear the headset properly.