[Ninto]

Is there any way to get non-DTS/DD content to upmix to output in digital format?

I have a HT-AS720 receiver that handles the digital output from XBMC Live (set to digital audio, default) fine for all content that is encoded in DTS or DD and gets passed through the optical out. That works fine when I set alsamixer correctly and switch XBMC to digital out.

However, when it's all set to digital, any content *not* encoded with DTS or DD doesn't play. If I leave the XBMC box alone and switch the receiver surround mode to PLII or anything else (while leaving the input as digital optical), then nothing works. If I switch everything over to analog, I get sound from everything fine, but obviously without any channel separation or the obvious clarity that comes from the all-digital end to end system.

Is there any way of "upmixing" non-DTS/DD content to such on the fly in XBMC under Ubuntu?

[MaximumFish]

I had this same problem, and it's all down to a confusing menu option in XBMC. The option in question is called something like "downmix multichannel audio to stereo". You'd think you want this disabled, right?

Well, no. If you don't turn this on then XBMC ends up outputting all audio to your receiver raw. Meaning if your receiver can't decode MP3, OGG, WMA etc itself then you get no sound.

Enable the option and, providing you have the DTS capable and/or Dolby Digital capable options enabled, then you'll get proper multichannel audio out of DTS/Dolby Digital encoded stuff, and stereo out of everything else. All through the digital connection.

[Ninto]

Thanks! That option was already enabled, but going back to that menu again (for the 100th time it seemed) made me think that maybe I had the wrong device selected.

As it was, I had default as the audio device, and IEC958 selected for passthrough.

Changing the regular audio device to IEC958 so that both passthrough and regular output went to digital out solved the issue.

Seems obvious now that I think about it, but thanks for pointing me in the right direction!

[earlneath]

I had this same problem, and it's all down to a confusing menu option in XBMC. The option in question is called something like "downmix multichannel audio to stereo". You'd think you want this disabled, right?

Well, no. If you don't turn this on then XBMC ends up outputting all audio to your receiver raw. Meaning if your receiver can't decode MP3, OGG, WMA etc itself then you get no sound.

Enable the option and, providing you have the DTS capable and/or Dolby Digital capable options enabled, then you'll get proper multichannel audio out of DTS/Dolby Digital encoded stuff, and stereo out of everything else. All through the digital connection.

Thanks MaximumFish, guess that shows sometimes it's good to experiment! I have been grappling with this issue and it hadn't occurred to me to try that!