Twitch only streams my voice and not the game?

Hello I'm currently streaming on my Mac book air on twitch. You only hear me through the mac book microphone but I can't hear the game and my buddy. I connected the mac book to my ps4. If someone can help it would be so nice. Our twitch name is: Haidhausir

Maybe you can explain it directly online

So you don't hear the game and your colleagues? What are you playing Ps4 or your Mac at all? If you do that on Mac, check the audio settings to see if everything is set appropriately so that your headset (if you use one) is set as the output device for all open programs / games