To broadcast sound from your DAW app to OBS you need to have an external audio interface. If you have it, follow the instructions below.
- Connect your external audio interface with mic to your Mac.
- Connect your headphones to the output in the audio interface.
- Go to the DAW preferences. Find your audio interface as an output channel.
- Go to your Mac settings > Sound > Output. Choose your audio interface device from the list.
- Go to OBS, add a Source and choose Audio Input Capture. Choose your audio interface from the list.
Now you are ready to stream high quality sound.