[mythtv-users] 3 audio devices on same time

[Jean-Yves Avenard]

On 9 December 2010 13:30, Josu Lazkano <josu.lazkano at gmail.com> wrote:

> I must configure it on the frontend or on the .asoundrc file?

in .asoundrc

>
> On XBMC I get it working with this file:
>
> pcm.!default {
> type plug
> slave {
> pcm "both"
> }
> }

then you use ALSA:default in mythtv (enter it manually) ; you can
click after you've typed ALSA:default on the scan button to see if it
works or not.

Make sure you select stereo though , and disable AC3 and DTS ; as it
won't work properly otherwise.

Passthrough would only work if all your device supports passthrough
and mythtv auto-setup of passthrough would probably not work (though
it may, I've never tested this kind of things).

If you get some warning in the log when myth is trying to set the
audio device for passthrough, it means it didn't work, then If you
want passthrough to work, you probably would have to override the
passthrough device ; and in your .asoundrc add a pcm that sets the
iec958 bit

Something like this:
pcm.hdmipassthrough {
        type hooks
        slave.pcm {
                type hw
                card 0
                device 0
        }
        hooks.0 {
                type ctl_elems
                hook_args [
                {
                        name "IEC958 Playback Default"
                        index 0
                        lock true
                        preserve true
                        value [ 0x06 0x82 0x00 0x01 ]
                }
                {
                        name "IEC958 Playback Switch"
                        index 0
                        lock true
                        preserve true
                        value true
                }
                ]
        }
}
or something similar and re-use the same type of rules you are currently using.
slaves.a {
pcm "hdmipassthrough"
channels 2
}

You will get better feedback in the alsa mailing list for this
advanced use of alsa.

JY