Audio output reverts from HDMI to system speakers after reboot or monitor turned off

[shawnlam]

HARDWARE:
My laptop is a Dell i7773.
I use a Vizio D40u-D1 television as a monitor.
I have the laptop display disabled, because I keep the laptop tucked away behind the monitor.

ISSUE 1:
After a reboot, rather than remember to output audio via HDMI, audio output reverts back to the "Speakers Built-in Audio" option.

ISSUE 2:
Power Management is configured to turn my monitor off after 15 minutes without use, but I never want my laptop to go to sleep. If the laptop remains powered on while the monitor is powered off, audio reverts back to the "Speakers Built-in Audio" option. This makes sense, because the monitor just turned off. Unfortunately, when I turn the monitor back on, audio does not automatically revert back to HDMI.

Right now, if I go to System Settings => Hardware => Sound, the Device options are:
- HDMI / DisplayPort Built-In Audio
- Speakers Built-in Audio

This issue is annoying, but I can live with it, if necessary. I know that plenty of others would like a resolution, assuming one is available. I definitely don't want to blacklist the system speakers, because, although rare, there are times when my laptop is not connected to my television.

--Shawn

EDIT: Somehow, I forgot to mention that I am running Linux Mint 19 Cinnamon.

[Citizen229]

START>SETTINGS>SESSION AND STARTUP
General tab check-auto save session on log out.
If you never log out like i do- click sessions tab and manually save the session at the bottom.

This should set your settings and they should not change.

[shawnlam]

Citizen229,

I want to follow your directions, but I can not find START. Perhaps I should have included that I am using Linux Mint 19.

--Shawn

[Citizen229]

Mint icon bottom left corner

[shawnlam]

Citizen229,

I am running LM19 with Cinnamon, and the instructions you provided just don't match.

After clicking MENU, then SYSTEM SETTINGS, there is no SESSION AND STARTUP. There is an option for STARTUP APPLICATIONS, but it has no General tab.
In SYSTEM SETTINGS, I can click on General, but there is no option for check auto save session on logout.

--Shawn

[lazarus]

Try this... (works in LM18.3x64 anyway. Don't know if it'll fix your problem, but it's the cinnamon equivalent to OP's suggestion.)

In a terminal execute sudo apt-get install dconf-tools
Then run dconf-editor
- In the left panel : select 'org > cinnamon > cinnamon-session'
- Check 'auto-save-session' on the right side of the config window
- Exit

Be very, very careful using this. You can really screw things up in there.

[shawnlam]

lazarus,

Thanks for that. I implemented your solution two days ago, and so far, it is working perfectly. I'll give it a while and report back.

-Shawn