In BA we used to have our own headsets issued, but it was determined that it really wasn't so anti-social to have aircraft headsets left on board. Cleaning pads are supplied. There may be a problem with some airlines where noise attenuating equipment is fitted to the aircraft and you plug your own private headset in, but I don't really take great interest in the technicalities. The headsets are not that bad and easy to clean. I don't think they last all that long anyway before going off for repair and coming back like new.