Cyril

Default output device

Ensuring output to the correct devices (audio & video) upon resume from suspend, or when display is disconnected and reconnected.

Audio

Setting a specific default audio device
start here: (no surprise) https://wiki.archlinux.org/index.php/PulseAudio/Examples#Set_the_default_output_source

Pre-req’s: alsa-utils pulseaudio-utils

Determine desired device name

• Setup audio as desired, and play a song or video.
• pacmd list-sinks (example output): ``` 1 sink(s) available.
  • index: 8 name: driver: flags: HARDWARE DECIBEL_VOLUME LATENCY DYNAMIC_LATENCY state: RUNNING [ ... ] ```

    Set desired output as default

• Edit /etc/pulse/default.pa
• Scroll to

  ### Make some devices default
  #set-default-sink output
  #set-default-source input  
  

• Change
  #set-default-sink output
  to:
  set-default-sink alsa_output.pci-0000_00_1b.0.hdmi-stereo

References

https://forums.linuxmint.com/viewtopic.php?t=288517
https://rastating.github.io/setting-default-audio-device-in-ubuntu-18-04/

or this? tries pacmd list-cards
https://forums.linuxmint.com/viewtopic.php?t=295237#p1645250

Video

Resume issues. Is this handled by x? do we need xrandr tricks? or does resume get information from KMS settings?
2019/09/27: finding out that Dell’s onboard video is stubbornly biased toward vga. I can’t get a status on the hdmi port no matter what I try.

KMS

kernel mode setting is the earliest point that we can specify the output.
It is not obvious what effect this may have on a graphical system resuming from suspend, but let’s start there.

kms force mode method #1, backed up by this other blog post.

1. With everything connected (and displaying) as desired, browse /sys/class/drm/ to find the card notation that you will need. example: /sys/class/drm/card0/card0-HDMI-A-1/
2. drm_kms_helper.edid_firmware=edid/1920x1080.bin and video=HDMI-A-1:1920x1080@60e to GRUB_CMDLINE_LINUX_DEFAULTof /etc/defaut/grub
3. or nomodeset video=HDMI1:1920x1080@60 Which would set the virtual terminal to 1920x1080, which is 1080p… And use the first HDMI port at that mode. ref
4. or video=VGA-1:d drm_kms_helper.edid_firmware=edid/1920x1080.bin video=HDMI-A-1:1920x1080@60e certain changes require update of initramfs via dracut -f
   for optiplex3010, try: uefi>maintenance>serr messaging [off]
   Cannot output to HDMI-A-1… cannot even status HDMI-A-1

xrandr

xrandr --verbose to get the name of the output and a working mode line