Changing volume from "Indicator Applet Complete" mutes alert sounds.

[chexmo]

Using Ubuntu MATE 20.04

Steps to reproduce:
    *open mate-volume-control and change alert volume
        (select a sound theme if there is no one selected)

    *try to produce any alert sound
        (I.e. open pluma and press up_key)
        (this should sound well)

    *then change volume from the "Indicator applet complete" using the left click of the mouse
        (by default, on the right side of the upper panel)

    *try to produce any alert sound
        (I.e. open pluma and press up_key)
        (NOW it makes NO alert sound)
        (If you open mate-volume-control, the settings of the alert sounds tab are changed despite i've not modified nothing myself)

[Jason LaFleur (jc-lafleur)]

Just did a fresh install of Ubuntu MATE 20.04 LTS this week and I can confirm this is still a problem.

I can go into Sound Settings - Sound Effects Tab and turn up the Alert Volume slider, I can hear the laert beep, but the volume is not changed no matter where the slider is set, and as soon as I close the Sound Settings window, the volume slider is reset to 0.

In fact, no sound settings are being saved after a reboot, logout, or resume from suspend or hibernate.

Every time I reboot, login, or resume from suspend, I have to manually go into sound settings and re-select the (HDMI 2) output of my video card as the source.. for some reason it keeps defaulting back to HDMI 1.

I have the on-board sound disabled in the bios, and it no longer shows up in the OS as a source, only my video card shows up as an audio source.

I am using a Nvidia GT 1030 card, running the latest tested proprietary driver (metapackage from nvidia-driver-470).