Call Indicator Suppression (CIS):
Discovery 665: Turn off the LED lights
Article ID :
This allows you to disable online and standby indicator lights. To disable these indicators: First have the headset paired with a handheld device then press the volume up button while turning the headset ON. To re-enable both indicator lights, turn the headset off, then press the volume up button again while turning the headset ON.
This process only disables online and standby indicator lights when headset is connected to mobile phone. All other indicator lights such as low battery, call reject, Power On/Off, will continue to function.
When you turn your headset or phone off, then on again, it will turn the LED back on the headset.