[20.04] Keyboard volume rendered useless because of root's userspace?

[Daniel LaSalle]

This is super minor. Yet it's super juicy:

Running 20.04-latest and with the following audio hardware configuration:

$ arecord -L
default
    Playback/recording through the PulseAudio sound server
surround21
    2.1 Surround output to Front and Subwoofer speakers
surround40
    4.0 Surround output to Front and Rear speakers
surround41
    4.1 Surround output to Front, Rear and Subwoofer speakers
surround50
    5.0 Surround output to Front, Center and Rear speakers
surround51
    5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71
    7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
null
    Discard all samples (playback) or generate zero samples (capture)
samplerate
    Rate Converter Plugin Using Samplerate Library
speexrate
    Rate Converter Plugin Using Speex Resampler
jack
    JACK Audio Connection Kit
oss
    Open Sound System
pulse
    PulseAudio Sound Server
upmix
    Plugin for channel upmix (4,6,8)
vdownmix
    Plugin for channel downmix (stereo) with a simple spacialization
usbstream:CARD=HDMI
    HDA ATI HDMI
    USB Stream Output
sysdefault:CARD=Generic
    HD-Audio Generic, ALC887-VD Analog
    Default Audio Device
front:CARD=Generic,DEV=0
    HD-Audio Generic, ALC887-VD Analog
    Front speakers
dmix:CARD=Generic,DEV=0
    HD-Audio Generic, ALC887-VD Analog
    Direct sample mixing device
dmix:CARD=Generic,DEV=2
    HD-Audio Generic, ALC887-VD Alt Analog
    Direct sample mixing device
dsnoop:CARD=Generic,DEV=0
    HD-Audio Generic, ALC887-VD Analog
    Direct sample snooping device
dsnoop:CARD=Generic,DEV=2
    HD-Audio Generic, ALC887-VD Alt Analog
    Direct sample snooping device
hw:CARD=Generic,DEV=0
    HD-Audio Generic, ALC887-VD Analog
    Direct hardware device without any conversions
hw:CARD=Generic,DEV=2
    HD-Audio Generic, ALC887-VD Alt Analog
    Direct hardware device without any conversions
plughw:CARD=Generic,DEV=0
    HD-Audio Generic, ALC887-VD Analog
    Hardware device with all software conversions
plughw:CARD=Generic,DEV=2
    HD-Audio Generic, ALC887-VD Alt Analog
    Hardware device with all software conversions
usbstream:CARD=Generic
    HD-Audio Generic
    USB Stream Output
$

$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: HDMI [HDA ATI HDMI], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 2: Generic [HD-Audio Generic], device 0: ALC887-VD Analog [ALC887-VD Analog]
  Subdevices: 0/1
  Subdevice #0: subdevice #0
card 2: Generic [HD-Audio Generic], device 1: ALC887-VD Digital [ALC887-VD Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
$

I am using card 2 off this last paste.

If I open a folder in caja containing videos and I play one of them using regular user and celluloid, volume knob on my keyboard works fine.

But if I then open any other video from an "Open as administrator" caja window, it will not play any sound(based on my non-expert status I can only assume that this happens because root space and user space do not share the same default audio settings??)

First question/problem/request: just like when applying monitor resolution changes into Control Center and applying them system wide, can you also please make it the same for the audio hardware output? As from a user perspective, it makes no sense at all to segregate the hardware values for sound when jumping in root in Ubuntu.

Now my real problem is if/when I close my caja window that is in priviledge mode and I then re-open a video w/ celluloid with my regular user, sounds of course works fine, but my keyboard volume knob isn't responding anymore even though I see the volume on screen going up and down when I scroll it, the sound waves do not actually increase nor decrease.

Some full moons ago, I posted something on UM forum which related of something similiar and here it is as a FYI: https://ubuntu-mate.community/t/19-10-problem-with-my-sound/20338/3

Furthermore, and again only as a FYI, I have blacklisted "hdi" and "snd_hda_codec_hdmi" in /etc/modprobe.d/snd-blacklist.conf and have rebooted my system to take effect. Hence maybe when you will try reproducing this you will also need to blacklist those 2 modules to get this volume control on your keyboard not listening...

And while you have your hands into the audio code, and as of why I had to blacklist hdi, here's another FYI: https://ubuntu-mate.community/t/20-04-the-year-is-2020-and-still-nobody-cares-for-you-usb-hid-v81-11-gamepad/22530

Thanks!