[mythtv-users] SPDIF output works for MythMusic, but not MythTV

Juan Jesús García de Soria Lucena skandalfo at gmail.com
Mon Mar 21 01:20:19 UTC 2005

Hi everyone.

> > Has anyone else had a similar problem?  Is anyone else using a cmpci
> > sound device succesfully using spdif output for all parts of myth?
> > The sound quality I get over spdif is obviously much better than the
> > analog connections, but right now I'm stuck using analog for
> > everything in order to avoid having to switch audio inputs when using
> > different parts of myth (because that's too much for the GF to handle
> > ;).

Having an NForce3 chipset, I experienced some problems when playing 5.1 DVD's.

In my case I used analog 5.1 output rather than optical, and ALSA was
forcing "Use Line-In as Surround" to be ON when playing throug the
surround51 "plugin".

I had to edit /usr/share/alsa/cards/NFORCE.conf in order to change

                        hooks.0 {
                                type ctl_elems
                                hook_args [
                                        name "Line-In As Surround"
                                        preserve true
                                        value true
                                        lock true
                                        optional true

To "value off" and things like that, since my mother board has analog
outputs for 5.1 that are independant from Line In / Mic.

Perhaps the configuration of your card is somehow forcing some flag
value (look for "hooks" sections) when you play through your specified


   Juan Jesús.

How can dreams come true? Is their type boolean?

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