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How to bypass AC3 on Mac mini?


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I'm new here and hope this isn't a stupid question.....


I have an Intel Mac mini running digital optical out to a modified LiTe DAC-AH (from COEM audio in Australia). It all works wonderfully except for one application.


I also run eyeTV and here in Australia, at least, HD broadcasts have AC3 (5 channel?) sound associated with them. The DAC doesn't seem to like this! I get pulsed static. When I ran the sound through USB (with a devilsound DAC I had on trial) this was not a problem. Either the devilsound can handle AC3 or it was not outputted as such via USB - I don't know.


In Audio Midi setup, it looks like I am setting it for 2 channel stereo output. This doesn't seem to help.


Any clues about what I need to do?





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That's what I've found:


For AC3 passthrough, open /Applications/Utilities/Terminal.app and type


defaults write com.cod3r.a52codec attemptPassthrough 1


To turn off AC3 passthrough, you type this instead:


defaults delete com.cod3r.a52codec attemptPassthrough


? MBP ? M2Tech hiFace ? Heed Q-PSU/Dactilus 2 ? Heed CanAmp ? Sennheiser HD650

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Thanks I.G.,

I tried this but it didn't work. When I tried the second command it told me that this default did not exist. So I tried the first one (same bad sound ) followed by the second one (same bad sound).


Any other clues?




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This has now been solved and I feel stupid. It was a simple preference setting in eyeTV that, I think, seems paradoxical.


You must select "system sound output" rather than "digital output" (even though both are outputted digitally in my case via toslink to my DAC) if you want 2 channel stereo.




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