Mac Pro - no sound via external speakers

[UtahWJR]

Do I need to use special speakers get get external sound from my late 2013MacPro via iTunes?

Connected speakers to line out (looks like speaker) next to headphone jack and get no sound. Changed preference settings to Line-out and no change. Speakers are powered Altec Lansing Series 5100 and both speakers and cable work fine on Lenovo work laptop.

 

[h9826790]

I don't have a nMP, but I think you can just plug that to the headphone jack.

 

[UtahWJR]

I don't have a nMP, but I think you can just plug that to the headphone jack.

Tried setup under a Win 7 VM and it works fine so it's something specific to OSX.

 

[Xzag]

I had a similar issue after installing Yosemite on a 5,1 recently. Condition of the patient was no sound coming out of the jack no matter what I plugged in (Headphones, speakers, etc. front or rear), and no system sounds no matter what buttons I pushed in system preferences. Sound was fine before the upgrade.

Decided to re-install Yosemite, and I noticed immediately that system and audio could be played from the system speaker when toggled that way from Syspref, but no music, or sound from speakers. I noticed that it defaulted to Airplaying on appleTV without me toggling it in iTunes after the re-install. Clicked off Airplay, and the Bose system fired up immediately.

So, #1, check the Airplay
#2, you might need to re-install OS (this worked for me).

Hope this helps you, or anyone else with a mute Mac Pro.