Voyager 510S/510SL/510SL+ Troubleshooting: Headset Doesn't Respond to Button Presses
My Headset No Longer Responds to Button Presses
The headset itself may need to be reset. A hardware reset of the headset can be accomplished by a simultaneous long press of the black Power/Mute button and the Speak Volume Down (-) key. Then let the headset rest for 1 minute before powering it back on.