Confusion about the so-called "Audio Input" device

It’s time to sort out my confusion about the so-called “Audio Input” in devices widget, as I’ve been trying to pass my mic to my signal appvm for the past couple of hours, which left me with only even more confusion than before.

My device in dom0 widget is described as “dom0:mic - Microphone”, which I can attach to all of my running vms.
My mic is registered in dom0 volume control, as can be seen on the screenshot, and the bar reacts to my voice.


My questions:

  1. Do I need to attach it to a vm like a block device, or is it supposed to work like audio output works (though vchan)?
  2. If you’re supposed to attach it, why is a mic present in my xfce pulseaudio plugin? Why is it out of sync with settings in volume control panel? Muting it in widget doesn’t mute it in volume control. What takes precedence?
  3. How is an appvm supposed to recognize this attached mic? As a vchan source or as something else? What command am I supposed to use in my appvm to see if it has recognized my mic?
  4. How secure is an action of attaching a mic to a vm?


SO apparently, you need to both attach mic to the appvm and also to change this appvms “record from” field from “Monitor of Built-in Audio Analog Stereo” to “Built-in Audio Analog Stereo” ie mic in my screenshot that reacts to my voice. VERY INTUITIVE INDEED. :man_facepalming:


The mic volume slider and mute button in pulseaudio plugin don’t do anything (except confuse people).
To change volume you need to do it in the panel on my screenshot.

To hide useless mic slider in widget you need to change “Analog Stereo Duplex” to “Analog Stereo Output” in “Configuration” panel of Volume Control. No you can’t hide it, because changing config to output completely removes input.

SO all that’s left is to answer my fourth question: How secure is it to attach a mic to a vm?