Is there an adapter which lets you use a USB headset with the controller? I would rather not have to buy a new headset.
USB headsets should work with PS4s using one of the USB ports, according to IGN: http://www.ign.com/wikis/playstation-4/Headset
However, I have seen one or two single 3.5mm to USB adapters. I don't know if those will work with the PS4 controllers, but the worst case scenario is to either buy a new headset, or to just plug your USB headset into the console (which will save you money).