How to select a specific device, stereo or headset when playing pcm data
The function you’re looking for is System::setDriver, which allows you to set the output driver for your Core FMOD System. This function only takes an int representing the index of the driver to set as output though - if you need to enumerate your drivers to know which to use as output, you can use System::getNumDrivers to get the total number of drivers, and then get info for each of them with System::getDriverInfo.