Mac Pro 2009 audio output not working- what can I try?!

[simulacrum]

Hi all,

I have a Mac Pro mid 2009 and the audio has stopped playing through any source, other than the internal speaker! The sound won't even play out of the headphone port. Here's the scoop. I have these awesome USB speakers:

And one day they just stopped working on me. However, they still show up as a valid output in Sound preferences, you could still select the Sound Sticks as usual through the Sound Output preference setting, but they just wouldn't make any noise. So, I put them in my closet and felt very sad about it. Now, a few months later I realize it wasn't just the speakers, the Mac Pro won't play sound through ANY external source, other than it's built in speaker! I confirmed that the Soundstick speakers are working just fine using another mac.

Interestingly enough, last night when I specified the "sound effect" output in the Sound Preferences tab to be the USB speakers, THAT works! Now I hear the sound effects through the USB soundsticks again. But it will not play any sound any source other than the Built in speaker, regardless of what's selected.

It seems like it must be a software problem but I have no idea what to try or do...? Any advice is greatly appreciated. Thanks!

 

[h9826790]

Try a PRAM reset if you are not using 3rd party SSD with Yosemite (or any other reason required to disable kext signing).

 

[simulacrum]

Try a PRAM reset if you are not using 3rd party SSD with Yosemite (or any other reason required to disable kext signing).

Thanks for your reply! I have tried that several times already I am afraid.

 

[Loa]

Hello,

Have you tried logging into another user? The root user?

Booting from a DVD/USB drive?

Any issues with the audio inputs?

Have you added any apps/plug-ins/system prefs that could mess with the audio in your Mac?

Loa

 

[crjackson2134]

I had this issue last year. I couldn't identify exactly what software caused this, but to confirm it was software rather than hardware, I booted into a live Linux DVD (Ubuntu). Sound worked perfectly. Since I do regular TM backups, I just rolled my system back 2 weeks and problem solved.

Have you installed any software (usually multimedia related) that may have affected this?

 

[initialsBB]

Also have a look at audio-midi setup in the utilities folder. It could be that a virtual interface was somehow setup, or that the master output has been lowered.