Created attachment 102410 [details]
Default boot option

Sorry for my poor english...

I have two sound cards in my Pc:

The motherboard's card (which is the one i want to use, using SPDIF)

and

The sound card of my Nvidia graphic's card, Nvidia GTX 970 with privative drivers (which is the one i don't want to use, using HDMI).


If i go to system preferences, multimedia, audio and video preferences, i can see in this place there is selected in the first position the right option
* Digital Surround 5.1

In this point, all other options are disabled.


But i have no sound ... If i now go to the Audio Hardware Configuration section, i can see in first choice:
* HDA Nvidia

Which is the output of the graphic's card using hdmi (which i do not need at all).

If I change that option to the correct one, which is in that case Internal Audio, Digital Surround Profile 5.1, everything works wonderfully until I restart the computer ...

On each reboot that option changes, and is always set by default HDA nvidia.

I've tried everything without finding the solution. In fact, if i open pavucontrol, everything is correct.