[mythtv-users] HDMI audio to TV - only 2-channel PCM available

[Phil Bridges]

On Sat, Aug 25, 2012 at 5:45 AM, Jean-Yves Avenard
<jean-yves at avenard.org> wrote:
> On 25 August 2012 05:07, Phil Bridges <gravityhammer at gmail.com> wrote:
>> I have had to set up my Zotac Ion disk less frontend again. I have the
>> 295.71 nVidia drivers.
>>
>> I have an LG LCD connected via HDMI. For some reason, the video card is now
>> only reporting 2.0 PCM available. As a result, the videos I have with only
>> DTS-HD audio are silent. I was able to play these on my previous install.
>> Any suggestions on where to look to fix this?
>
> A TV will typically only support PCM 2.0... It's perfectly normal that
> is all myth is showing.
>
> DTS-HD will usually contain a DTS-Core stream that myth/ffmpeg can
> decode. There are no open-source DTS-HD decoder. So unless you can do
> passthrough, you will get at best DTS Core 5.1
>
> You shouldn't hear silence, unless it's a DTS-HD only stream, in which
> case, at this stage, there's nothing you can do

Thanks for the response.  In contrast, my other diskless frontend
(connected to a Panasonic plasma) has no problem playing the same
file.  What is interesting is that the frontend with the LG is listing
the ALSA connection as "connected", but the Panasonic is not.

Here's what mediainfo lists about audio:

Audio
ID                                       : 2
Format                                   : DTS
Format/Info                              : Digital Theater Systems
Format profile                           : MA / Core
Codec ID                                 : A_DTS
Duration                                 : 1h 33mn
Bit rate mode                            : Variable
Bit rate                                 : 1 561 Kbps / 1 510 Kbps
Channel(s)                               : 6 channels
Channel positions                        : Front: L C R, Side: L R, LFE
Sampling rate                            : 48.0 KHz
Bit depth                                : 24 bits
Compression mode                         : Lossless / Lossy
Language                                 : English
Default                                  : Yes
Forced                                   : No

Might this be a case where I need to go through the "plughw" route?