Dell Latitude e7470 strange audio „crackle“ on fresh ubuntu 16.04 LTS

I notice a strange crackle while booting my new Dell Latitude E7470 with a fresh ubuntu on it. It happens twice on every boot. Once before entering the password and once after successful login.

I found a solution by toying around with the alsamixer.

For me the solution is to disable the loopback channel.

Start alsamixer with this command:
alsamixer -c0

  • Naviagate to the Loopback channel rightmost with arrow-key
  • Disable the Channel by pressing the arrow-down-key once
  • Save and quit the alsamixer with ESC


After that you need to reboot. The crackle is gone.

Have fun…

Configuring ISC-DHCP on Ubuntu 14.04 with Webmin-Panel

I am requested to install a Linux- Dhcp server in our network for some subnets. After setting up everything, I ran into the following problem. It seems that Webmin does not recognise the service-start during the boot-sequence of ubuntu. If you click start in webmin-panel you start a second process of isc-dhcpd-service.
Reasons for that is a false webmin module-config, which comes with default parameter for an old configuration.

To solve that, you need to modify the module-config to the following parameter.

First open the Module-Config-Page:

Change the highlighted fields to this:

Command to start DHCP server:service isc-dhcp-server start
Command to stop DHCP server:service isc-dhcp-server stop
Command to apply configuration:service isc-dhcp-server restart
Path to DHCP server PID file:/var/run/dhcp-server/

Click save. After that everything works for me as expected.


Change Citrix Receiver Default Keyboard Layout to German

Citrix Receiver works perfect in ubuntu 14.04. now. Only problem is the Keyboard-Layout if you would like to use different layout than US.

Changing the Layout is easy. Just open the terminal and navigate to the Citrix settings folder. In my case it is:
cd ~/.ICAClient/
open the file wfclient.ini
nano wfclient.ini
search for Paramter KeyboardLayout
change KeyboardLayout=(User Profile) to KeyboardLayout=GERMAN

Restart Citrix-Client.


Install Skype with Unity-Indicator in Ubuntu 15.04.

Go to and download the ubuntu 12.04 multiarch package. Open the .deb-File with Software-Center and install it.

After installing you may want have a nice indicator icon. You need to install the support for that with:
sudo apt-get install sni-qt:i386

Restart skype and you are done. In my Unity it looks pretty nice now…

Solve Ubuntu Video Tearing

I had in all video applications (VLC, XBMC, KODI …) problems with video tearing.

While watching a movie there are anoying vertical stripes in scenes with fast moving content or during camera movements.

Specially in KODI and VLC the problem occurs.

The solution is quite easy. Just do the following:

sudo nano /usr/share/lightdm/lightdm.conf.d/50-xserver-command.conf

Add the -bs option to the xserver line. After adding the content of the file looks like that:
# Dump core
xserver-command=X -bs -core

Do a reboot and enjoy your movies.

This is tested on my Dell Latitude E7440 with Ubuntu 14.04 . You may also need to change the file again, after upgrading to a newer Ubunut version.



To solve the problem in Ubuntu 15.04 with Intel-Chipset under my Dell Latitude E7440:

sudo apt-get install mesa-utils
sudo mkdir /etc/X11/xorg.conf.d/
echo -e ‚Section „Device“\n Identifier „Intel Graphics“\n Driver „Intel“\n Option „AccelMethod“ „sna“\n Option „TearFree“ „true“\nEndSection‘ | sudo tee /etc/X11/xorg.conf.d/20-intel.conf


In Ubuntu 14.04.3 LTS the above solutions suddenly stops working for me. After some reading I find the following which works again for me.

You need to create the file /etc/X11/xorg.conf

TearFree is disabled by default. To enable it add in /etc/X11/xorg.conf:

Section "Device"
   Identifier  "Intel Graphics"
   Driver      "intel"
   Option      "AccelMethod" "sna"
   Option      "TearFree" "true"

Same problem suddenly happens again. No solution above works for me anymore.
So here is the very new fix that worked for me so far:
sudo apt-add-repository ppa:timo-jyrinki/ppa
sudo apt-get update
sudo apt-get install libsdl1.2debian

Temperature Control on Dell Latitude E7440 under Ubuntu 14.04.2 LTS

I collect many informations how to control the fans under ubuntu now. Here is what works for me at the moment.


1st Problem: Without additional fan-control tool my Dell Latitude E7440 runs quiet until a special temeperature and then speeds up the fan to full speed forever.

2nd Problem:With i8kmon installed and the service started, the fan-control lasts only a few seconds and is then controled again from BIOS.

3rd Problem: With fan-control tool i8kmon installed with default settings my Latitude runs very quiet the whole time. But because dell has a CPU-Throttling-Policy which you are not able to control, the Latitude runs until a special temperature and then the BIOS scales down the CPU to the minimum frequency. The result is a freezing Desktop until the temperature cools down to a ridiculously low point at about 45°C.


1st: Install i8kutils and lm-sensors
sudo apt-get install i8kutils lm-sensors

2nd: Disable BIOS-Fan-Control (Without Warranty)
sudo apt-get install gcc-4.6-multilib
(on 16.04 I need to change the above line to „sudo apt-get install gcc-multilib„)
cd ~
mkdir .bin
cd .bin
sudo apt-get source i8kutils
sudo apt-get build-dep i8kutils
tar xf i8kutils_1.41.tar.xz
cd i8kutils-1.41
gcc -g -O2 -Wall -I. -o smm -m32 smm.c
sudo ./smm 30a3
sudo cp smm /usr/sbin/

In the next step, we setup i8kmon to stop the bios-fan-control automatically
sudo nano /etc/init.d/i8kmon

Find the following:
case „$1“ in
            log_daemon_msg „Starting $DESC“ „$NAME“

And change it into:
case „$1“ in
        /usr/sbin/smm 30a3
            log_daemon_msg „Starting $DESC“ „$NAME“

In the same file find the following:
        log_daemon_msg „Stopping $DESC“ „$NAME“

And change it into:
        /usr/sbin/smm 31a3
        log_daemon_msg „Stopping $DESC“ „$NAME“

This will disable Bios-Fan-Control directly while starting i8kmon. And enable it while shutting down the service i8kmon.

3rd: To prevent scaling down the CPU edit the configuration of i8kmon
find the example-file i8kmon.conf
sudo find / -name ‚i8kmon.conf‘

In my case i find the file in my user-home: /home/rod/.bin/i8kutils-1.41/i8kmon.conf
Now copy the file to /etc/i8kmon.conf. Change your directoryname!
cp /home/rod/.bin/i8kutils-1.41/i8kmon.conf /etc/

Modify the file with nano:
sudo nano /etc/i8kmon.conf

Change to the following:

# Automatic fan control, override with –auto option
set config(auto)        1

# Automatic fan control, override with –auto option
set config(auto)        1

set config(0)  {{-1 0}  -1  30  -1  30}
set config(1)  {{-1 0}  30  50  30  50}
set config(2)  {{-1 1}  45  60  45  60}
set config(3)  {{-1 2}  55 128  55 128}

# end of file

The last block in this file controls the fan-speed based on temperatures. Here is how to read the block:
{{ -1 0} -1 30 -1 30}
{{ first_fan_speed second_fan_speed} low_temp_on_ac high_temp_on_ac low_temp_on_bat high_temp_on_bat}

Because the Dell Latitude has no first fan, we can setup the first fan always to „-1“

The temperatures are the first test now. I will Update this post after gathering some experience.

KODI 14.2 stops playing Amazon Prime Videos

After normal upgrading my Ubuntu, Amazon Prime Addon in Kodi suddenly stops working. There was no error-message shown in kodi at all, it just happens nothing after starting a movie.

After some log review i found an error in kodi.log under „~/.kodi/temp“ that says: „ERROR: Unable to load“

Thats the reason. Just install the package and enjoy again Amazon Prime movies.

sudo apt-get install librtmp1

Dell Latitude E7440 Bios A14

Seit heute nutze ich das Bios A14 auf meinem Dell Latitude E7440. Herunterzuladen ist das Bios-File hier.

Die Beschreibung verheißt schon einmal Gutes. „Fixed Typing on internal Keyboard abnormally with Linux OS.“

Ich teste das neue Bios jetzt schon seit ca. 10 Stunden und soweit scheinen die nervigen Fehler alle behoben zu sein.

UPDATE: Nach 4 Tagen kann ich bestätigen, der Keyboard-Error ist verschwunden.

Aktuelle Konfiguration: Ubuntu 14.04.2 LTS Upstream-Kernel 3.18.2-031802-generic

Installation i8kutils unter Ubuntu 14.04.1 LTS für Dell Latitude E7440

Das Latitude E7440 hat ein Problem nach der Installation von i8kfanutils. Der Lüfter wird nur immer kurzzeitig gedrosselt. Nach einer Sekunde übernimmt anscheinend die Hardware wieder die Kontrolle und regelt den Lüfter wieder hoch. Das ganze scheint zu toggeln.

Einen Workaround dazu habe ich mir aus mehreren Einträgen im Internet zusammen gesucht.

Die Installation werde ich in den nächsten Tagen hier beschreiben.

Hier bereits mal unaufbereitetet die einzelnen Schritte:

sudo apt-get install gcc-4.6-multilib
mkdir bin
cd bin
sudo apt-get source i8kutils
sudo apt-get build-dep i8kutils
tar xf i8kutils_1.41.tar.xz
cd i8kutils-1.41
gcc -g -O2 -Wall -I. -o smm -m32 smm.c
sudo ./smm 30a3

sudo cp smm /usr/sbin/
sudo nano /etc/init.d/i8kmon

/etc/init.d/i8kmon by adding „/usr/sbin/smm 30a3“ to right below the „start)“ line. Later on, I put „smm 31a3“ right below the „stop)“ line (just experimenting), and found that after resuming, the power button, brightness buttons, and wireless switch work normally while the fan is still being controlled by i8kmon. However, the CPU down-scaling still happens once in a while.