Plantronics Blackwire 225 - Inline Call Control; Adjust Your Headset Volume

Press the answer/end button on the headset inline control to answer or end a call (mobile phone
only).
Slide the volume control up on the headset inline control to increase listening volume.
Slide the volume control down on the headset inline control to decrease listening volume.
Inline call control
Adjust Your Headset
Volume
8