Anyone know the Audio mixing method?

API CallLegService.pushNewStream(legID, streamName) can be invoked multiple time to push multiple audio streams(with unique names) from FMS to FMG on single call.  FMG mixes them in real time and delivers the mixed audio to remote participant of the call.

     Example:

               myLegService.pushNewStream(<legID>, <streamToMix1>);

               myLegService.pushNewStream(<legID>, <streamToMix2>);