[mattlach]

Hey all,
 
So, my fiance really liked the sound quality of my DAC/Amp/Headphone combo on my computer, so having suddenly created an audiophile I set her up with a nice little starter package of her own for her birthday, consisting of a Schiit Modi 2 Uber DAC, Schiit Asgard Amp and a 250 Ohm set of Beyerdynamic DT770 Pro headphones.
 
This is for her Late 2013 27" iMac (iMac 14,2)
 
The DAC supports USB, SPDIF and Optical Toslink.  Because USB inherently has timing and interpolation issues when it comes to audio (I know this is a matter of argument, and I don't want to go there in this post, suffice it to say that I am a believer in the school of "optical".) I opted for the optical toslink connector, and ordered a mini optical to toslink cable.
 
The system sounds great, and she loves it, except for one little problem.
 
Whenever you plug the mini-optical cable into the 3.5mm port on the back of the Mac, it becomes the only audio output listed in the list of devices in System Preferences -> Sound.  "Internal Speakers" are listed there before you plug it in, but plug it in and they disappear.
 
This poses an issue.  Constantly unplugging and replugging cable is both inconvenient and difficult due to its obscured position on the back of the mac (it's partially blocked by her second monitor), and it is also not very good for the optical cable long term (and possibly not for the switch in the mac port either.
 
Ideally, one should be able to just leave it plugged in and switch between the two with a click of the mouse, and this is how it works if you use Bootcamp and install Windows (and Linux too, for that matter), so we know it isn't a hardware limitation, but rather a software limitation.
 
Something in either the OS itself, or in the driver (kext?) is - presumably for ease of use - disabling the Internal Speakers when something is plugged in, so Apple get's fewer "why am I not hearing sound" complaints from clueless users.   Not a bad design choice, but there absolutely HAS TO be a way to override this behavior and return control to the user. The question is how?
 
Switching to USB, or buying any additional hardware (speakers or otherwise) is not an acceptable solution for something that should just work in software.
 
I have been clicking through everything I can find looking for advanced options to no avail.
 
Has anyone else run into this problem?   How did you resolve it?   Are there maybe further advanced configuration files in text format inside the kexts?  Or maybe a third party audio kext exists one can use?
 
I welcome any ideas at all.
 
Thanks,
Matt

 

[Qwazi]

The third post at the following thread seem to offer a solution to your problem: 
http://apple.stackexchange.com/questions/6510/use-internal-speakers-with-others-plugged-in
 
once you can reveal the internal speakers as a selectable audio-source alongside the headphones it's a simple tank to make a script connected to a keyboard shortcut or an icon for switching between the devices.

 

[mattlach]

  The third post at the following thread seem to offer a solution to your problem: 
http://apple.stackexchange.com/questions/6510/use-internal-speakers-with-others-plugged-in
 
once you can reveal the internal speakers as a selectable audio-source alongside the headphones it's a simple tank to make a script connected to a keyboard shortcut or an icon for switching between the devices.

 
Yeah, unfortunately the files he is suggesting one download from mega, are no longer available.
 
That and, I'm not a huge fan of blindly downloading and installing something from an uncontrolled source like mega.  Sounds like a pretty guaranteed way to wind up with a keylogger or worse.