[mythtv-users] DTS Passthrough

[Douglas Peale]

On 06/29/2010 08:49 PM, mythtv wrote:
> I just upgraded from 0.22 to 0.23.  In 0.22, I had DTS passthrough working
> on my Zotac ION board going to my DTS receiver over the coax output.  Both
> DTS and AC3 worked fine for mkv files in both myth and mplayer.  DTS tracks
> would show up as DTS on the receiver so I had that confirmation before.
> 
> Since upgrading to 0.23, I no longer get any DTS streams to the receiver.
> The receiver shows the format of the stream and everything I'm getting now
> is Dolby Digital.  It seems to be re-encoding the DTS stream to AC3 because
> I DO have surround sound, just no longer in DTS format.  mplayer still
> continues to work with DTS but I would rather play everything back with
> Myth's internal player.
> 
> I've tried as many combinations of settings that I can think of and I've
> searched the lists, since I thought I recalled seeing someone else with this
> problem before, but I have not found a solution.  Can anyone help with the
> settings?  Or is this even possible?
> 
> My current settings are:
> 
> Audio output device: ALSA:spdif
> Speakers configuration: 5.1
> Upconvert stereo to 5.1: unchecked
> Upmix: Best
> Digital output device: ALSA:iec958:{ AES0 0x02 }
> Dolby Digital: checked
> DTS: checked
> Advanced Audio Config: unchecked
> 
> I also have Use internal volume controls unchecked
> 
> Thanks for any help.
> 

Try ALSA:default (you may have to manually type that in).
I've never gotten digital pass through on ALSA:iec958 to work, all I ever get out of that is noise.
I have had digital pass through work on ALSA:default, but I always had to toggle the main mute button on the mixer before I got
anything but silence out of it.
I finally switched to the analog outputs on my motherboard because they support 7.1, and digital pass through usually is at best
5.1, and very rarely 6.1 with DTS-es discrete. Also it does not require messing with the mute button to make it work.