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I'm trying to use the optical audio output of my motherboard to send the sound to my AV Receiver.

I only see the front channels received by my AV.

Indeed rear channels don't seem to be activated.

Sound settings

How can I activate the rear channels ?

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1 Answer

You can't. S/pdif support PCM, AC3 and DTS (if your decoder support them) PCM only support stereo up to 24bit/192khz

AC3 and DTS support surround. But they are patented technologies and not open-source friendly. As far as I know, ther is no way to get Ubuntu to transcode on the fly to AC3 or DTS to feed S/PDIF

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