prevent imac from shutting down while playing music

Hi Huskies_mlspl!

There is an app for that! I use it all the time!

Get Amphetamine from the Mac App Store (click here).

When you have downloaded it and opened it up, it will ask you some questions and give you tips.

When you have finished all that, there should be new little icon in your iMac's toolbar that looks like this:

Click on it and select "preferences."

At the top of the preferences window, select triggers,

then check "enable triggers."

Click the + sign at the bottom of the window.

Name your trigger (something like "Play Music" or "Music").

Next, where it says "Select a criterion to configure," select "app," and check the box next to "use app criterion." Now open the app you want to play music from (iTunes, Spotify, etc.)

then go back to the preferences window and select it from the list.

Before pressing save, you can select either "Allow display to sleep when this trigger activates a session" or "allow screen saver to run when this trigger activates a session," or both, or none!

(note that if the display goes to sleep the computer will still be on).

Then press save!

On the top of the preferences window you can click on any of the others and customize the settings to your liking.

Now whenever this app is open, your computer will not sleep, but it will sleep if the app has been quit.

I really hope this helps!

Check System Preferences > Energy Saver and make sure "Prevent computer from…" is checked.

One solution would be to open terminal (command+space bar to bring up spotlight and type "terminal", or you can find it in the launchpad) and type the command: "caffeinate". This command will prevent your iMac from sleeping. Once you're finished listening to your music, you can use control+C in the terminal window to end the caffeinate process, or you can just close the terminal window and it will ask you if you want to terminate the caffeinate process; click terminate and your system will return to normal.

Does the same thing happen if you don't play the music through the Apple TV? I don't own one so I can't check or check any settings the Apple TV may have.

I do not know but will check on it, problem is that it shuts down everything and I have to login all over again

Is you Mac shutting down or going to sleep? What app are you using to play music, iTunes or something else? What do you have to re-login to?