In order to communicate with the audio hardware on a given computer, Simulink uses the open source PortAudio library. The PortAudio library supports a range of APIs designed to communicate with the audio hardware on a given platform. For Windows, the default is DirectSound, for Linux, the default is ALSA, and for Mac there is only one choice.
To determine the audio hardware API currently selected, type the following command in the MATLAB command prompt.
getpref('dsp','portaudioHostApi')
The output is a scalar indicating the choice of the API. 1 — DirectSound 3 — ASIO 7 — OSS 8 — ALSA 11 — WDM-KS To select a particular API, type the following command in the MATLAB command prompt.
setpref('dsp','portaudioHostApi',N)
It might be possible that the API that was setup on your computer is different than the one that is required by your operating system.
The above information is present in the following documentation link: