Dealing with the madness of combo ports

If your Mac's audio suddenly silences, it may likely be that your headphones port has been taken over by its hidden and usually silent partner. The solution requires a low-tech device: a wooden toothpick.

The other day my MacBook Pro became silent and nothing I did seemed to fix it. First, I looked at settings in the Sound Preferences pane, which showed that it was set to Digital Output, a setting that was unfamiliar. Everything else, volume controls and the usual settings for the onboard speakers were either missing or grayed out.

I then opened the Audio Midi preference and checked the Audio Devices settings, which should show Built-in Output as the setting. But no, same problem. Digital silence.

Was this a software issue? I logged out of my usual user account and into one that I've created for testing such things. It's bare-bones but pure. It also was silent. So, the problem was hardware related.

After a while, I unplugged the notebook, picked it up and looked into the audio out port. It was glowing red. I had never noticed this behavior before. Since this was during the day and my MacBook Pro sits on a stand away from the surface of the desk, I hadn't noticed the change. It was odd.

A search offered the answer: it seems that the headphones port is dual-use or combo. Most of the time, it works as expected provided analog audio out to headphones or external speakers. However, it also serves as a minijack TOSLINK fiber optic connector, which Apple calls "optical digital output." This high-performance cable supports all kinds of multichannel audio.

The TOSLINK connector is just a skosh (0.5mm) longer than the stereo analog 3.5mm minijack. You can use a TOSLINK minijack cable or an inexpensive adapter that connects to less-expensive TOSLINK cable with plugs.

But the changeover to TOSLINK can happen at any time. It seems that when removing the headphones with a yank after editing some audio, I must have accidentally flicked a switch inside the port. The MacBook Pro thought that there was still a TOSLINK connector attached even though there wasn't anything plugged into the port.

Plugging and unplugging the headphones didn't help. And I tried sticking in a small screwdriver and a large paperclip. No change.

A thread on Apple's discussion boards suggested a wooden toothpick. For some reason, this worked. I also read that a small plastic coffee straw works.

If I had my MacBook Pro connected to a TOSLINK receiver, I know I would appreciate this dual-connector port. But I don't. So for me, this behavior belongs in the It's-not-a-bug, it's-a-feature department.