27" LED Display Audio Problems

[Cynicalone]

I noticed today that the speakers on my 27" LED Display had quit working.

I usually keep my Mac Pro connected to a home stereo receiver, and don't use the built in speakers so I don't know if this had been a problem since day one or not.

I tried a bunch of different things, restart, disconnect the USB cable, disconnect the MiniDisplay Port cable. Disconnect the secondary display, and various combinations of connect this and remove that. Finally I decided to do the old Apple standby and try and reset the SMC. That worked and the audio now works.

Strange thing is the LED Display update Apple released a few days ago to enable audio over the MiniDisplay port appears not to be working. At least my computer doesn't see it as an option. Just USB audio from the display.

This is really mostly a none issue for me since I don't use the built in speakers, but I thought I would post it in case others are seeing the problem with the new displays.

Anyone actually have audio working over the MiniDisplay Port?

 

[DFTU101]

Just checking, you did the software update for the 27 inch screen? I think it came out last week or so?

Also, under system preferences, sound, there's no choice for "display audio"?

 

[Cynicalone]

Just checking, you did the software update for the 27 inch screen? I think it came out last week or so?

Also, under system preferences, sound, there's no choice for "display audio"?

Yes this one here http://support.apple.com/kb/HT4293

According to Apple it should look like this...

But mine still looks like this...

 

[bluesteel]

Have you connected a mouse or keyboard to the back of your display to see if those USB ports work? I bought a 27" LED the other day and returned it because the USB ports on the rear of the display were not working. I was also having a problem with the display speakers exactly as you are.

 

[Cynicalone]

Have you connected a mouse or keyboard to the back of your display to see if those USB ports work? I bought a 27" LED the other day and returned it because the USB ports on the rear of the display were not working. I was also having a problem with the display speakers exactly as you are.

Yes after reading your post in the other thread I connected my keyboard directly to the display. It has worked perfectly.

I don't really know what to make of it. It hasn't occurred again yet.

I think the audio over MiniDisplay Port problem has been narrowed down to me using an extension cable that doesn't carry audio.

I have actually been playing some audio threw the speakers trying to make the problem occur again. Don't know very strange in a new display.

 

[bluesteel]

I think the audio over MiniDisplay Port problem has been narrowed down to me using an extension cable that doesn't carry audio.

sounds like this could have been your culprit.

great, i'm glad your display is now working. at least you don't have to return it cause that is always a pain. i also noticed your using your display with a Mac Pro. I was using mine with a 2010 Macbook Pro.

good luck with the new display

 

[a.y.n]

Ok, this is a different problem, I have a earlier unibody MacBook Pro that does not have audio from the Mini DisplayPort. When I got the 27" ACD audio worked over USB, but today I installed the 27" ACD software update, and now the audio does NOT work over USB. I've bounced the Mac and tried a few things, I believe the 27" ACD software update that gives you ambient light sensor and minidp audio support to your ACD broke audio over USB.

This is what I saw in the logs:

System Preferences[332]: Error ^P trying to set sOut device to 264

--Andrew