We need a simple way to transfer audio output/input between two settings at the click of a button during a call, similar to Skype for Business, so that users can answer calls on their "speakerphone" (PC speakers / desktop mic) and toggle to a headset when desired. We have a customer who is frustrated because they purchased many headsets and desktop microphones, while under the impression that they could easily toggle between headset and speakers with the 3CX softphone app on Windows. The only way we have found to work around this, is using a bluetooth headset with a 3rd party bluetooth dongle. If you set the PC speakers/mic to default devices in Windows sound control panel, then connect a bluetooth headset, and set it as default, then every time you physically turn the bluetooth headset off, the audio will jump back over to the speakers. This is not reliable however, as some headsets have poor audio quality with 3rd party dongles, and if you use a dongle made by the manufacturer (such as Plantronics headsets with their dongle) then Windows never detects the device as powering off, and the audio will simply go nowhere when you turn off the headset.