A computer controller for a plurality of audio devices and audio applications and a method of control is disclosed. An audio subsystem is disclosed allowing multiple applications executed by the computer to exchange audio signals with multiple sound interface devices. A first sound interface device to emit a first loudspeaker sound signal in dependence on the first loudspeaker audio signal. The sound signal is received by an intermediate application and from the audio subsystem a first microphone audio signal depending on a first microphone sound signal received by the first sound interface device. An intermediate application causes a second sound interface device to emit a second loudspeaker sound signal in dependence on the second loudspeaker audio signal. This allows a user to conduct a softphone call using one headset connected to the computer, while the user's supervisor may listen in on the softphone call using a second headset connected to the same computer, however, without requiring any changes of the computer's hardware, its operating system or the softphone application.