HDMI audio reverts to internal speakers (when turning amp or TV off).

Select the A/V amp as the audio output device in the Sound settings in System Preferences rather than the TV. It should only revert to the internal speakers if it doesn't detect an external audio device. Check the HDMI settings in your amp for the input the mini is connected to if the problem continues.

capaho wrote:
Select the A/V amp as the audio output device in the Sound settings in System Preferences rather than the TV. It should only revert to the internal speakers if it doesn't detect an external audio device. Check the HDMI settings in your amp for the input the mini is connected to if the problem continues.

The Mac mini loses contact with the external audio device in this case because the external audio device is an AV Receiver which has either been switched to 'listen' to a different source or the final link in the chain (the TV) has been turned off. (The Mac is sending the audio over HDMI to the AV Receiver.)

A possible solution for Bingggo would be to get a Gefen HDMI Detective, this is supposed to trick the Mac in to thinking the link is still live even if it is not.

See http://www.gefen.com/kvm/dproduct.jsp?prod_id=8005

The OP said that his mini shows the TV as the audio device when it is on, which is likely a result of the A/V amp settings. The mini should always see the amp and not the TV. OS X will switch to the internal speakers if no external device is detected, and it doesn't make much sense to expect to be able to play audio through an external device that is switched off.

What happens when you do as Capaho says?

Regarding the suggestion of using an HDMI Detective: I'm not sure that will fix this situation. While that device successfully mimics a particular monitor/display, I'm not sure that it does this for audio as well as video. I don't have the HDMI version to play with, but I do have the DVI version, which passes HDMI sound (when using HDMI to DVI cabling). I will have to experiment with this, for my own edification.

capaho wrote:
The OP said that his mini shows the TV as the audio device when it is on, which is likely a result of the A/V amp settings. The mini should always see the amp and not the TV. OS X will switch to the internal speakers if no external device is detected, and it doesn't make much sense to expect to be able to play audio through an external device that is switched off.

I have used a Mac mini with a Sony AV Receiver and a Sony TV. When the AV Receiver is switched to a different source (so it is no longer listening to the Mac mini), the Mac mini no longer gets a signal back and therefore thinks nothing is connected. Hence it (in this case) reverts the audio to a valid output which is the built-in speaker. The Gefen HDMI Detective should make the Mac mini think the link is still live (this is the purpose of this Gefen product) and the Mac mini should hopefully therefore not switch back to the built-in audio.

As far as I can see, AV Receivers do not work like VGA or DVI KVM (Keyboard/Video/Mouse) switchboxes in that such switchboxes normally keep the VGA/DVI signal live back to all the computers. KVM switchboxes do this because they know they are working with computers that need this, but AV Receivers are mainly intended to be used with consumer electronics which normally do not care about this. In this case we are trying to use a computer in a consumer electronics application and need to workaround the computers limitations.

Note to Bingggo the DVI Detective does not pass sound since DVI cannot carry sound.

I inadvertently switched away from my mini once with Internet radio playing and it didn't default to the internal speakers. When I switched back to the mini, music resumed playing from my Onkyo A/V amp.

It may be that switching to internal speakers in such a case depends on the specific output device, but why would anyone want to leave audio playing on the mini if they're switching away from the audio output device?

John Lockwood wrote:
...The Gefen HDMI Detective should make the Mac mini think the link is still live (this is the purpose of this Gefen product) and the Mac mini should hopefully therefore not switch back to the built-in audio...

To my knowledge, that's not guaranteed. Because, not all implementations of EDID include audio information. It's possible that because the Detective makes the Mac think that a video display device is still there, that nothing else should change. But it's equally possible that if the EDID information in question doesn't specify audio capability, that the Mac will still look elsewhere for an audio interface.

As far as I can see, AV Receivers do not work like VGA or DVI KVM (Keyboard/Video/Mouse) switchboxes in that such switchboxes normally keep the VGA/DVI signal live back to all the computers.

Just be careful about mixing the terms KVM and switchbox. While they seem similar, a switchbox is typically a passive device that does straight switching. Whereas a KVM uses active circuitry to mimic (to varying degrees) keyboard, video and mouse connections to each computer connected (as you mentioned).

I just want to be careful about having people led into thinking that a switchbox is no different than a more sophisticated KVM.

...but AV Receivers are mainly intended to be used with consumer electronics which normally do not care about this. In this case we are trying to use a computer in a consumer electronics application and need to workaround the computers limitations.

Well, you're right that the electronics up the HDMI chain do not typically care whether or not an HDMI device is present all the time. But the situation we have here is that the Mac very much cares about what it sees connected to the HDMI port. And when it sees nothing, it's not sure what to do.

Note to Bingggo the DVI Detective does not pass sound since DVI cannot carry sound.

Actually, it does. As I mentioned in another thread on this forum, I have a DVI Detective and have passed sound through it (connections: mac mini HDMI to HDMI-DVI adapter to DVI detective to DVI-HDMI cable to HDMI receiver).

Now it's entirely likely that the DVI Detective can't properly mimic any audio information that may be included in an HDMI display's EDID information. But it does pass the HDMI audio bitstream unfettered. And it certainly does fine with replicating the HDMI video EDID information. All this I can attest to, since I have been using the DVI Detective for about 3 years now. (First with my C2D Mini and now with my 2010 Mini.)

I'm new to the forum, and have very little technical expertise, but maybe i can offer a solution. I bought the new mini primarily for the HDMI port, but immediately ran into this same trouble because I have it switched through my Panasonic receiver. No matter what I do or try the mini won't consistently deliver audio to the receiver unless i leave it switched on constantly. Becasue I use it, like many of you, for different feeds at different times, that cannot work for me.

But this does: Kanex iAdapt 51 MDP to HDMI w/ 5.1 Channel Digital Audio.

It's a little pricey, but it works. Simple and foolproof. I've been using it for weeks, and it works every time. Simple. Took about 5 minutes to set up, following the instructions on the website.

I can't tell you how much time I spent in various discussion threads looking for an answer. Then i found a reference to this in a Plex forum. Problem solved. I admit that on one hand I find it irksome that I need an adapter for my new mini, but on the other i guess i'm more interested in getting my media center/server to work flawlessly than i am in complaining about Apple not being able to deliver a product that works with every configuration known to man !!!

eabecker wrote:
I'm new to the forum, and have very little technical expertise, but maybe i can offer a solution. I bought the new mini primarily for the HDMI port, but immediately ran into this same trouble because I have it switched through my Panasonic receiver. No matter what I do or try the mini won't consistently deliver audio to the receiver unless i leave it switched on constantly. Becasue I use it, like many of you, for different feeds at different times, that cannot work for me.

But this does: Kanex iAdapt 51 MDP to HDMI w/ 5.1 Channel Digital Audio.

The reason the above works, is because as far as the Mac mini is concerned it is using its built-in TOS-Link all the time rather than the HDMI link. The problem being discussed is if you try to use the audio directly through the HDMI.

I agree your solution is worthy of consideration. It would probably cost less than the Gefen HDMI Detective. Furthermore, it has emerged that the audio capabilities of the Mac mini HDMI port are not as impressive as hoped. The only thing extra it does compared to TOS-Link is that it can support 7.1 PCM audio (TOS-Link is limited to 5.1), neither can do Dolby HD. For the Mac mini HDMI this is a limitation of the current Nvidia chipset apparently, TOS-Link will never support Dolby HD due to bandwidth limitations.

I am finding that my 2010 Mini is now also exhibiting this same behavior upon every startup. Since I only restart weekly, I didn't become aware of it being a consistent problem until a couple of restarts. But now, like clockwork, a restart results in the audio output switching to the Mini's internal speaker.

This happens even though I always do the restart while my HDMI receiver and display are powered on and set to the inputs for the Mini.

My workaround has been to install an AppleScript that automatically changes the output to the HDMI connection. I found the the script on the Mac OSX Hints site. You can paste it into your AppleScript Editor and save it as an application.

You'll need to change the entry that says "SOUNDSOURCEGOESHERE" to the actual sound output name that relates to your HDMI device. (This is no doubt case sensitive, so be exact.)

Also make sure you turn on support for assistive devices in the Universal Access control panel, or this script will not work.

Once you have saved this script as an application, you can set that app as a login item, so that the script will automatically run on startup.


tell application "System Preferences" to activate
tell application "System Events"
get properties
tell process "System Preferences"
click menu item "Sound" of menu "View" of menu bar 1
delay 2
set theRows to every row of table 1 of scroll area 1 of ¬
tab group 1 of window "sound"
set theOutputs to {} as list
repeat with aRow in theRows
if (value of text field 1 of aRow as text) ¬
is equal to "SOUNDSOURCEGOESHERE" then
set selected of aRow to true
exit repeat
end if
end repeat
end tell
end tell
tell application "System Preferences" to quit

I'm about to buy the new Mac Mini and was planning to plug it into my home theatre, however not through the receiver but through the plasma and run sound back to the receiver through HDMI Audio Return Channel (ARC).

That should work right? Has anyone tried that? Any loss of sound quality?

First, I should followup regarding the original discussion...

The AppleScript I outlined above stopped working for me. I didn't bother figuring out why. I was simply tired of dealing with the B.S. behavior of this new mini and HDMI audio.

I switched to the Mini DisplayPort and connected it to my DVI Detective. The audio is routed to my Denon receiver via mini-Toslink.

This setup is reliable.

Matt2.0 wrote:
I'm about to buy the new Mac Mini and was planning to plug it into my home theatre, however not through the receiver but through the plasma and run sound back to the receiver through HDMI Audio Return Channel (ARC).

That should work right? Has anyone tried that? Any loss of sound quality?

Yes, absolutely. Because the Mini will always be seeing the same HDMI EDID information, whether the receiver is on, or off.

What about a script that detects the change in output (to internal speakers) and mutes the volume. That would solve the problem for me and wouldn't require more equipment.

This script should work to mute the computer, but I don't know how to detect a change in the sound output. Any suggestions?

set isMuted to output muted of (get volume settings)
set newMuted to not isMuted
set volume output muted newMuted

As the mini switches back to the big speakers when the amp is back on that could be another triggering event that sets the output to not muted.

Thoughts?

Thanks! Dylan