I've tried, unsuccessfully, to find documentation on using the button(s) on wired headsets (not Bluetooth) with this phone. Through trial-and-error, here's what I've found so far: If the phone is IDLE: single click - starts music player double click - calls someone (I think the most recent person in your call list) If the phone is RINGING: single click - answers phone If you are IN A CALL: single click - hangs up call. If you are LISTENING TO MUSIC: single click - stops music FYI, I use a "Blackberry OEM headset" (stereo + microphone + single button). Hopefully, this will help others looking for the same information. Anyone have any more information?