Hi SAILU571,
If you'd like to know more about using more than two channels in Audio MIDI Setup on Mac, these steps might help.
What happens when you attempt the steps below?
1. In the Audio MIDI Setup app on your Mac, select an audio output device in the list, then click Configure Speakers.
If your output device has multiple streams, they’re listed at the top of the window.
To change how you view the speaker configuration, click View, then choose a view. For Isometric or Side view, you can drag the 3D view to rotate it 360 degrees.
2. Click the Configuration pop-up menu, then choose a configuration, such as Stereo or 5.1 Surround.
If you have five front speakers and two rear speakers, choose 7.1 Surround. If you have three front speakers and four rear speakers, choose 7.1 Rear Surround.
3. For each speaker in the list, click the Channel pop-up menu, then choose a channel to assign to the speaker.
You can click a speaker in the 3D view to highlight it in the list.
Tip: If your output device has multiple streams offering multiple channels, it may be difficult to find the channel you want in the pop-up menu. At the top of the window, you can deselect the checkbox for each stream you don’t want to use, so their channels aren’t shown in the pop-up menu.
The information above is from Set up external speakers for stereo or surround sound in Audio MIDI Setup on Mac. If you get the "Configure Speakers" option then continue with the rest of the steps in the link to finish setting up speaker to channel assignments.
We hope that helps with your question and take care!
