Sound only from Mac, not monitors

[Tom Cutlass]

...everything was working fine. Now Protools/NI plays only thorough Mac speakers. I saw something about Apple that if you plug into the headphone input it changes the set up. I did do that recently. Can't get more info.
If I go to System Preferences, sound, output, it says ProTools and MBox do not have outputs.
Help?!

[Darryl Ramm]

Please try to provide more useful information..

Start up at the "help us help you" link up the top of every DUC page. Read and try to follow what is asked for there.

"headphone input" you mean headphone output, aka headphone socket? What exactly is plugged into the headphone socket? make/model headphone or whatever it is? The socked on the Mac or on the Mbox? You've now unplugged that right and output from the monitors still does not work as you expect?

What exact monitors do you have connected to what exactly how, using what types of cables/connectors. The monitors are tuned on and the volume on them and the interface/OS X is turned up? If you plug headphones in to the Mbox headphone out and turn up the headphone volume on the Mbox do you head anything in the headphones?

There are three different generation of Mbox products, and multiple models in each generation. Which exact one do you have? Post a link to an online data sheet or exact photo if not sure.

What Mac model number/date name? What exact OS X version? What Mbox thingy driver version? What exactly is selected as the playback engine in Pro Tools?

Anything else changed? OS X upgrade itself? (you have auto upgrade disabled right?.. if not now is the time to properly optimized you system).

The leading reason for Avid interfaces drivers to stop working is the Mac sleep/suspends while the interface is connected and the Mbox driver hangs, which is braindead but expected behavior. This will happen when the Mac times out and sleeps/suspends or you close the lid on a MacBook Pro. Reboot OS X and try again. And if the computer is sleeping itself you have not optimized the system for Pro Tools properly, go back and go over the installation documentation again. What exactly is he playback engine set to in Setup>Playback Engine. Do not assume it is correct, Pro Tools can and will change this on you.

What other standard troubleshooting have you tried? Some things to try: Different USB? ports. Different USB or Firewire cables. Reinstalling the interface drivers. Try a USB 2 powered Hub if the Mac is all USB 3? Most of that should not really require discussion here (its largely part of the standard troubleshooting stuff), but just let us know *exactly* what you have tied.

[Darryl Ramm]

System Preferences>sound>output is pretty useless, you should be looking in the Audio/Midi Setup utility. Audio Window for a better view of sound devices OS X sees.