A Sound Question

Mid 2012 Mac Pro

3.2 Quad Core intel Xeon

32 GB 1033 DDR3

(Sapphire Technologies) Radeon RX 580 8192 MB


Since the Mojave-mandated upgrade to a new graphics card, I have a choice of poor picture quality and sound using the Line Out Port and a DVI adapter from the graphics card to the HDMI port on the LED TV/Monitor I'm using.


OR, I can get superb picture and no sound using HDMI out to TV. Line Out does not work as an input to the TV Audio-In. Line out does work for an external speaker, but I'd like to restore the cleaner approach of Mac to TV


In System Prefs/Sound: No HDMI selection.


Any suggestions would be appreciated.

Mac Pro, macOS Mojave (10.14), null

Posted on Oct 13, 2018 1:30 PM

Reply
Question marked as Top-ranking reply

Posted on Oct 15, 2018 6:39 AM

Apple have for some utterly insane 😕 reason chosen to deliberately disable HDMI audio on video cards in the classic Mac Pro.


The KEXT referred to by Eau Rouge or more typically a slightly newer 1.1 version had been a relatively easy fix for Sierra and earlier versions of High Sierra. However with later versions of High Sierra i.e. 10.13.4 and later and the current Mojave version Apple have gone even further to make it even harder to re-enable HDMI audio support.


Currently you need to do the following -


  1. Disable SIP protection to allow loading an unsigned KEXT i.e. the HDMI Audio 1.1 KEXT
  2. Edit the AppleHDAController.kext to patch in the product code for your video card
  3. Install the HDMI Audio 1.1 KEXT


This post and thread discusses this workaround - GUIDE: HDMI Audio | Page 28 | MacRumors Forums

13 replies
Question marked as Top-ranking reply

Oct 15, 2018 6:39 AM in response to Wally12

Apple have for some utterly insane 😕 reason chosen to deliberately disable HDMI audio on video cards in the classic Mac Pro.


The KEXT referred to by Eau Rouge or more typically a slightly newer 1.1 version had been a relatively easy fix for Sierra and earlier versions of High Sierra. However with later versions of High Sierra i.e. 10.13.4 and later and the current Mojave version Apple have gone even further to make it even harder to re-enable HDMI audio support.


Currently you need to do the following -


  1. Disable SIP protection to allow loading an unsigned KEXT i.e. the HDMI Audio 1.1 KEXT
  2. Edit the AppleHDAController.kext to patch in the product code for your video card
  3. Install the HDMI Audio 1.1 KEXT


This post and thread discusses this workaround - GUIDE: HDMI Audio | Page 28 | MacRumors Forums

Oct 16, 2018 8:08 PM in response to John Lockwood

Here was my impetus in choosing the card(s) to upgrade to Mojave:

How to upgrade to macOS Mojave - Apple Support

Of course this was based on the install intercept saying I had to have a Metal capable Graphics Card

Mac Pro introduced in late 2013, plus mid-2010 or mid-2012 (mine) models with a recommended Metal-capable graphics card.

"These specific third-party graphics cards are Metal-capable and compatible with macOS Mojave on Mac Pro (Mid 2010) and Mac Pro (Mid 2012):"

  • MSI Gaming Radeon RX 560 128-bit 4GB GDRR5 ( Tried it - No Sound - returned)
  • SAPPHIRE Radeon PULSE RX 580 8GB GDDR5 (Currently installed and Sapphire belatedly telling me no audio support)
  • SAPPHIRE Radeon HD 7950 Mac Edition
  • NVIDIA Quadro K5000 for Mac
  • NVIDIA GeForce GTX 680 Mac Edition

The rest, below the RX580, begin to get into the $$$ range. As an Apple believer, I'd have assumed (yes, I know) that these had been vetted and would be a lovely plug-and-play to bring Mojave to your Mac. And why would I begin to question the potential for issues with audio output? After all, Apple says these are 'good'...... and all of them eclipse the performance specs of the original ATI Radeon 5870 I removed. 'Shoulda' been a slam dunk. HDMI to HDMI and modern technology at its finest.


Now waiting for the aforementioned adapter to see if I can patch it sideways and make it work.

"You could use a HDMI Audio Inserter, such as

https://www.monoprice.com/product?p_id=13347

to add optical audio to the HDMI from the graphics card." From Malcom's reply.


And, if not, use the clone drive to return to High Sierra and put the ATI back in. Or decide to invest even more and see if there's a capable audio/video/Metal card that will only set me back a car payment or two....

Oct 16, 2018 6:37 PM in response to Wally12

Wally12 - I don't know which specific Sapphire card you are referring to here.


The only video cards that were available in both Mac and PC versions were the AMD Radeon HD 7950 and the Nvidia GTX-680. Newer cards like the AMD R9-280x and RX-580 have only been available in PC versions.


I can absolutely say that the AMD Radeon HD 7950 Mac edition card is capable in hardware of doing audio via HDMI because not only does this work on this unaltered card in Windows via Boot Camp in the Mac Pro it also works in macOS High Sierra with the HDMI Audio 1.1 kext.

Oct 14, 2018 8:46 AM in response to Eau Rouge

I have been hoping it would show up. I have only seen the model of the TV in the Color Profile prefs from the old original graphics card, but never as a sound output choice. I've rebooted at almost every change of setting or hardware change.


The only time I get sound is using a DVI adapter out to HDMI, and using the 3.5mm patch cord from the Mac to the TV. BUT, then the picture goes garishly purple cast and won't adjust no matter how many settings I change. Line out works for headphones and speakers.


Expensive thought, but could this TV be beyond its years for the graphics card to register it? The TV works fine on TV mode with the cable box. It's about the only other change I have not tried, save calling Sapphire Technologies tomorrow when they're open, which I will do next, I guess.

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