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Cyberpunk_Is_Bae

Member

Registered: 2020-03-23

Posts: 36

Interesting / Unknown Input Devices

Hi thanks for any help with this.

I installed a new game and I have the following listed input devices:

Pulseaudio
Monitor of Built-in Audio Analog Stereo
Default System Device
Default Communication Device
Monitor of GP107GL High Definition Audio Controller Digi... // Scrolls off the view

That last one is especially concerning because it looks to a layman like me, like the monitor has some kind of mic in it...

I also have in $ arecord -l

**** List of CAPTURE Hardware Devices ****
card 1: PCH [HDA Intel PCH], device 0: ALC1150 Analog [ALC1150 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: PCH [HDA Intel PCH], device 2: ALC1150 Alt Analog [ALC1150 Alt Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

I also have in $ alsamixer > F6:

- (default)
HDA Intel HDMI
HDA Intel PCH
HDA NVidia

I also installed Audacity to take a look, and while I can't get a signal, it also has inputs I don't recognize:

HDA Intel PCH: ALC1150 Analog (hw 1,0)
HDA Intel PCH: ALC1150 Alt Analog (hw 1,2)
pipewire
pulse
default

Now this seems like a lot of recording devices (I am shy, I don't like to talk on mic in online games) for a system I specifically set up to be silent.  After checking, my monitor is connected by DisplayPort (large, NVidia card) not HDMI, so it is possible something is coming off of it, but I checked the spec and my monitor should not have an inbuilt mic.

Thank you for any help.

<they're listening omg.gif>

Last edited by Cyberpunk_Is_Bae (2020-09-05 19:24:23)

joanbrugueram

Member

Registered: 2018-11-12

Posts: 21

Re: Interesting / Unknown Input Devices

I believe "Monitor of X" recording devices are just loopback devices for a playback device "X". So it should just be a recording device that you can use to capture whatever is coming out of your speakers/headphones. Nothing weird.

You could also try to install something like Audacity to verify that it is indeed not recording any external audio.

Cyberpunk_Is_Bae

Member

Registered: 2020-03-23

Posts: 36

Re: Interesting / Unknown Input Devices

I believe "Monitor of X" recording devices are just loopback devices for a playback device "X". So it should just be a recording device that you can use to capture whatever is coming out of your speakers/headphones. Nothing weird.

You could also try to install something like Audacity to verify that it is indeed not recording any external audio.

Thanks.

Audacity gives a very strange error on both HDA devices (above > OP) when I press record:

Error opening recording device.
Error code: -9997 Invalid sample rate.

Still normal / expected?

Last edited by Cyberpunk_Is_Bae (2020-09-05 20:49:43)

loqs

Member

Registered: 2014-03-06

Posts: 17,372

Re: Interesting / Unknown Input Devices

pacmd list-sources

Should provide more information on the source.  I expect GP107GL is the HDMI audio controller on a Pascal series Nvidia GPU.

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,738

Re: Interesting / Unknown Input Devices

If you want to record from audacity while you are using pulse you should select the pulse device and then manipulate from a pulse mixer. As joanbrugueram has noted, in pulse terms the "monitor of your hdmi card" is a loopback device where you can record what you hear/is sent to the hdmi output, most commonly used by e.g. screen recording software to have something to record audio with.

The two actual mic/analog devices are seperate input recording jacks of your own built in sound card, the other two relevant ALSA -> pulse/pipewire compatibility sinks, the "default" is ALSA's default device, configured to be pulse if you have pulseaudio-alsa installed otherwise will default to whatever your hw:0,0 mic is.

So far just from a general standpoint, nothing of this is out of the ordinary. What are your specific concerns/understandings here?

Last edited by V1del (2020-09-08 09:09:05)