Bionic "amplified" sound controls do not sync with volume slider

[Erick Brunzell]

This is intentionally a duplicate of bug #1817485 to collect info on a fresh vanilla install of 18.04.2 after updating to prove that Ubuntu's default session is also effected. I just wanted to collect all pertinent logs to prove that this was in fact an unmolested install.

As in the previously filed bug report once over-amplification is switched on only the volume slider in the top panel actually increases the sound above 100%. The slider in the sound settings UI will not increase the sound above 100%. The keyboard hot-keys are also effected in the flashback session, but NOT the default Ubuntu session.

So if using the flashback session, in use as an HTPC, if you're streaming content in full screen and have the sound set above 100%, when a blaring loud commercial comes on and you turn the volume down with the keyboard hot keys you can't use the keyboard hot-keys to return to that over-amplified state. In the default Ubuntu session the hot-keys function as expected.

I'm attaching a screenshot. A logout is necessary for the over-amplification setting to take effect so the steps to reproduce are as follows:

(1) Open System Settings > Sound
(2) Toggle Over-Amplification to On
(3) logout and then log back into the default session (this is required)
(4) Open System Settings > Sound and toggle the volume slider to the left, then all the way to the right.
(5) Click on the volume icon in the top panel and you'll see that it's only at about 66% - obviously the two should "sync" but do not

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: gnome-control-center 1:3.28.2-0ubuntu0.18.04.2
ProcVersionSignature: Ubuntu 4.18.0-15.16~18.04.1-generic 4.18.20
Uname: Linux 4.18.0-15-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.5
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Mon Feb 25 14:25:01 2019
InstallationDate: Installed on 2019-02-25 (0 days ago)
InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-control-center
UpgradeStatus: No upgrade log present (probably fresh install)

[Erick Brunzell (lbsolost)]

Actually only a logout is necessary for the UI and volume slider to respond to the amp change. So I'll add steps to reproduce.

[Erick Brunzell (lbsolost)]

One more difference between the default and flashback sessions is that the keyboard hot-keys DO work in the default Ubuntu session, but NOT in the flashback session. So that makes this even a lower priority, and passes part of the responsibility onto the flashback devs.