Ubuntu on Dell Inspiron 9400

These may or may not affect you:

Screen flickering
This would appear if you have installed the nVidia proprietary drivers, no matter what version. The screen randomly flickers and it's annoying.

Open a terminal and type

sudo gedit /etc/X11/xorg.conf

Add the line

Option "RegistryDwords" "PowerMizerEnable=0x1; PerfLevelSrc=0x2222; PowerMizerDefaultAC=0x1"

to the "Device" section, so it looks like this:

Section "Device"
 Identifier "Default Device"
 Driver "nvidia"
 Option "NoLogo" "True"
 Option "RegistryDwords" "PowerMizerEnable=0x1; PerfLevelSrc=0x2222; PowerMizerDefaultAC=0x1"
EndSection

Reboot and it should be in order. Note that in case the bug reappears, which has happened to me, the xorg.conf reverted to default because I was tampering with dual-screen setup.


Audio problems – volume jumping from 0–100 % in one click

Open a terminal and type

sudo gedit /usr/share/pulseaudio/alsa-mixer/paths/analog-output-lfe-on-mono.conf

Change:

[Element Hardware Master]
switch = mute
volume = merge
override-map.1 = all
override-map.2 = all-left,all-right

[Element Master]
switch = mute
volume = merge
override-map.1 = all-no-lfe
override-map.2 = all-left,all-right

[Element Master Mono]
required = any
switch = mute
volume = merge
override-map.1 = lfe
override-map.2 = lfe,lfe

into:

[Element PCM]
switch = mute
volume = merge
override-map.1 = all
override-map.2 = all-left,all-right

[Element LFE]
switch = mute
volume = merge
override-map.1 = lfe
override-map.2 = lfe,lfe

[Element Master]
switch = mute
volume = merge
override-map.1 = all
override-map.2 = all-left,all-right

Remove:

[Element LFE]
switch = off
volume = off

Restart pulseaudio (pulseaudio -k).

Open sound preferences and choose from the output tab the "Analog Output (LFE)" connector.


Credit goes to whoever wrote this.