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keyboard volume control don't work with HDMI audio...

Hi (sorry if my english is not very good, cause I'm brazilian),

I bought the new Mac Mini, the very new, with a HDMI port. I'm using the computer with a Samsung TV-Monitor, model P2270HN, using a HDMI to HDMI cable. All is working fine, I configured and calibrated the image. The question is with the audio: I set the sound to work with the Monitor-TV speakers, using the HDMI cable. All works fine, the thing is, when I do that, the keyboard MAC OS volume control don't work, and I just can set the volume using the remote control of the Samsung Monitor-TV.

I think is strange, because Itunes and Quicktime, for example, continue with their own volume control. What is more practical than use the remote control of the TV-Monitor.

There's a way to make the keyboard volume control work? Or that's just the way it is and that's it?

Mac Mini, Mac OS X (10.6.3)

Posted on Aug 1, 2010 8:23 PM

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Posted on Aug 28, 2010 11:27 AM

You can always use the cmd+up-arrow & cmd + down-arrow when in itunes for volume control.
Don't know if thats any help?
13 replies

Aug 24, 2017 7:52 AM in response to appeltje-E

appeltje-E wrote:


Check out http://soundcontrolapp.com/ or https://staticz.com/add-keyboard-volume-controls/


Thanks for posting these I had not seen them. As you are undoubtedly aware the way both work is by first converting the sound to analogue, then altering the volume by modifying the analogue waveform, then converting back to digital and sending the modified signal on its way. (As per my previous reply.)


I have since my previous reply now found an application for the Mac that extends the ability to use CEC - Consumer Electronic Control signals down the HDMI cable to not only Plex and KodiTV but in theory any Mac application. You still need the USB CEC adapter as per https://www.pulse-eight.com/p/104/usb-hdmi-cec-adapter and then this new free software called Couch Slouch from here http://couch-slouch.com/compatibility/ extends its usefulness to any Mac program. Doing volume control this way avoids the extra digital-to-analogue-to-digital conversions.

Jul 4, 2015 7:27 AM in response to Pablo Cabistani

Follow the advice of this article:

http://www.mattmontag.com/music/enable-mac-volume-control-for-hdmi-and-displaypo rt-audio-devices


  1. Use Soundflower (3rd party) - install (http://rogueamoeba.com/freebies/soundflower/)
  2. Launch Soundflower
  3. Choose Soundflower 2ch -> your monitor
  4. Go to Sound preferences and choose SoundFlower 2ch
  5. You should be set to go

Jul 6, 2015 4:27 AM in response to Pablo Cabistani

Apple take point of view that if the audio interface is a digital connection, e.g. TOS-Link, HDMI, or Displayport then being digital one should try and not do anything that would cause any changes to that digital stream so that it arrives in a pure pristine unaltered form on the final output device. For those unaware to change the volume one has to change the amplitude of the analogue waveform (sound is an analogue waveform) which if the signal is digital means it has to be first converted to analogue, then have the analogue wave modified, then convert it back to digital. Any time a conversion or alteration takes place there is a small unavoidable loss of quality. Apple therefore intend that either your TV or your AV Receiver or other final output device i.e. the device which does the final conversion from digital back to analogue is responsible for the volume control. This means that the conversion process only has to happen once for example the TV converts it to analogue, lets you alter the volume while it is analogue and the plays it via its speakers again while it is analogue, there is no digital --> analogue --> analogue repeated conversion.


As such normally the volume menu in the menubar will be greyed out and the keyboard controls ineffective if the audio connection is digital. I have found that for example the Sound preference pane allows you to alter the 'beep' volume level but does not let you alter the overall system volume which is what applies to other programs.


It sounds like Windows will default to allowing all volumes to be altered even if a digital connection is in use but this means the original signal is being changed by Windows as described above. In fact with the Windows approach the digital --> analogue conversion is worse than you think as below


Sound needs to have volume altered

Sound is converted from digital to analogue on computer

Sound has its amplitude changed

Sound is converted back to digital on computer

Sounds is sent to TV

TV converts sound to analogue

TV plays back sound


This compares to the Apple approach


Sound needs to have volume altered

Sound is sent as unaltered digital to TV

TV converts sound to analogue

TV is used to alter volume/amplitude

TV plays back sound


So with Windows it has had to be converted between analogue and digital twice. It can even be worse than that, if the sound is being generated by the computer rather than being played from an existing digital audio file, then another set of analogue/digital conversions may also have to take place. Even if one ignores the very small quality loss this all entails it also causes a small amount of 'latency' as well with each step.


So, I can see some merits from Apple's approach and I can also see some merits from the Windows approach.


The ideal solution would be for Apple and others to support a standard called CEC - Consumer Electronics Control. This is a way for a device - in this case the computer to send a control signal down the HDMI cable telling the device at the other end e.g. the TV or AV Receiver to alter the volume, this would allow the Mac keyboard volume controls to trigger a signal to the TV to alter the volume. With this approach all the additional analogue/digital conversions are avoided but the user still gets the same effective control via the keyboard etc. on the Mac. Unfortunately CEC requires hardware level support and no Macs currently support CEC. I have suggested this as a future change to Apple and the more other people make the same request the more likely it is to happen.


There is a third-party accessory that can 'insert' CEC commands but most software will not support it. Have a look at https://www.pulse-eight.com/p/104/usb-hdmi-cec-adapter this does work with the Kodi software even on a Mac. (Kodi was formerly known as XBMC.)


PS. The reason why an approach like using SoundFlower might work is that SoundFlower is effectively 'virtualising' the sound output connection and as a result the Mac no longer counts it as a standard digital interface like HDMI etc. Effectively using SoundFlower makes the Mac use the same approach as Windows as described above.

keyboard volume control don't work with HDMI audio...

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