Audio Questions

[Vlad Markov]

On Wed, 24 Mar 2021 15:27:09 -0400
Aim via freebsd-questions <freebsd-questions at freebsd.org> wrote:

> 
> When I added a webcam last night my audio stopped working. I was very surprised.
> 
> I got it working again but have no clue what I did. In loader.conf I did the following changes:
> 
> # Original
> # hint.hdac.0.cad0.nid17.config="as=1 seq=15"
> # hint.hdac.0.cad0.nid22.config="as=1 seq=0"
> # end of original
> hint.hdac.0.cad0.nid21.config="as=1 seq=15"
> hint.hdac.0.cad0.nid28.config="as=1 seq=0"
> 
> Is there something I can read that explains all these elements? What is a NID, for example? I just guessed after reading dmesg.

The man page sent me here: Intel High Definition Audio specification

I now know cad = codec address, nid = node id. A cad has many nids which correspond to inputs/outputs.

The man page now made sense.

cad0.nid28 is line out. A seq of 0 turned it off. I switched to a seq of 15 which implements jack detection.

cad0.nid21 was a disconnected microphone, it needed no value.

In /etc/sysctl.conf setting "hw.snd.verbose=4" let me see everything.

Still have no idea why things changed.

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