Sennheiser SD series User Manual page 11

Product overview of the headsets
10 | SD Series - User Guide
Overview of the LEDs of the headset
SD Office – HS SD Pro1/Pro2 – HS
Headset LED
lights up blue
flashes blue slowly
flashes 3 times red
repeatedly
is off
flashes blue/red
Meaning
Headset is being charged in the base
station
Active link to base station
Rechargeable battery is almost flat
Standby mode or headset is switched off
Headset's rechargeable battery is fully
charged
Special pairing mode/direction of the
volume up/down function of the
Audio button is being changed
Pairing of an additional headset with the
base station/conference call