[mythtv-users] Mythbuntu 12.04 - No HDMI Audio [SOLVED]

[HP-mini]

On Mon, 2015-12-28 at 05:38 +1100, Kingsley Turner wrote:
> A note for the archive, while I still remember ...
> 
> On mythbuntu 12.04 we were having some issues with HDMI sound output.
> 
> Everything looked OK, the drivers, the wires etc.  But audio just did not 
> output.
> 
> Checking in alsamixer (on 12.04) there was no HDMI option at all.
> 
> After reading a bunch of (now quite old) forum posts, we found a curious one 
> that suggested un-muting an IEC958 device in alsamixer.
> 
> Doing so fixed the problem.
> 
> So it looks like alsamixer on Ubuntu / Mythbuntu 12.04 labels the HDMI audio 
> device as IEC958.
> And in some cases (ours at least) it was muted by default.
> 
> hope this helps someone
> 
> -kt

HDMI supports IEC958 encoded bitstream (AC3/DTS etc) & discrete PCM
multi-channel.
Most TVs only support 2 ch PCM & encoded bitstream.