If you are hearing sound from the computer you first need to make sure you have already installed the drivers for the AudioBox. You will most likely remember, but if not open the Windows Device Manager and you should see a listing for "PreSonus USB Audio Devices, AudioBox" or something like that. If not install or re-install the AudioBox driver, not the Studio One software.
If you have the driver installed, then go to the windows menu -> control panel -> hardware and sound -> select "Sound". You will see two tabs there labeled "Playback" and "Recording". Select the "AudioBox USB Audio" in each of the Playback and Recording tabs and set it to be the default device. If you are using a DAW application to playback or record, also go to the settings in the application and make sure that the playback and recording settings also are selected for ASIO USB AudioBox also.