[LAU] Jack & pulse...knickers in a twist.

Len Ovens len at ovenwerks.net
Tue Jun 5 21:20:25 CEST 2018


On Tue, 5 Jun 2018, Mac wrote:

> The piece I don't see is, assuming there is a device with 5 outputs, how do you
> get jack to create playback_3, _4 etc.
> 
> (I get aplay doesn't show jack, but, for example aplay -L lists (this is a
> shortened list):
> 
> front:CARD=PCH,DEV=0
>     HDA Intel PCH, ALC892 Analog
>     Front speakers
> surround71:CARD=PCH,DEV=0
>     HDA Intel PCH, ALC892 Analog
>     7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
> hw:CARD=PCH,DEV=0
>     HDA Intel PCH, ALC892 Analog
>     Direct hardware device without any conversions
> hw:CARD=PCH,DEV=1
>     HDA Intel PCH, ALC892 Digital
>     Direct hardware device without any conversions
> 
> How does jack decide to only do 2 playback_1,_2?
> 
> I take it there is something else in alsa startup that says provide for example
> surround71

I do not know if jack will accept surround71:PCH,0 for device. I do not 
know the mechanism by which it switches either. You are getting beyond my 
knowledge. It would not hurt to try. The other thing to look at may be 
hdajackretask. This shows what the audio jacks are currently being used 
for. I do not know if changing "blue Line In" to "Rear Side" will change 
hw:HDA from 2.0 to 4.0 for example. but it may be worth a try. Setting 
physical jacks to do surround operation may be all it takes.

In my case the real answer is I don't know. I tend to disable any internal 
audio device to clear up one more thing that may interfere with "real 
audio".


--
Len Ovens
www.ovenwerks.net


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