Ubuntu – Cannot play DVDs with ubuntu 18.04

I used to have Ubuntu 16.04 and I always could play DVDs with VLC. However, after an update to 18.04 I cannot do that anymore.

I have already tried the following:

sudo apt install ubuntu-restricted-extras   
sudo apt install libavcodec-extra    
sudo apt install libdvd-pkg    
sudo dpkg-reconfigure libdvd-pkg

I have also installed libdvdread4 and libdvdnav4 and libdvdcss2.

But when after I put the disc in and try to load it in VLC, I see the opening screen of the DVD for a few seconds after which it disappears again.

Can anyone help? thanks!

this is what appears in the terminal:

katrien@katrien-ThinkPad-T400:~$ vlc
VLC media player 3.0.4 Vetinari (revision 3.0.4-0-gf615db6332)
[000055c5a5985570] main libvlc: Vlc draait met de standaardinterface. Gebruik 'cvlc' om vlc zonder interface te gebruiken.
[000055c5a59894e0] main playlist: playlist is empty
libdvdnav: Using dvdnav version 6.0.0
libdvdread: Attempting to use device /dev/sr0 mounted on /media/katrien/NAAR_BUITEN for CSS authentication
libdvdnav: Can't read name block. Probably not a DVD-ROM device.
libdvdnav: vm: dvd_read_name failed
libdvdnav: DVD disk reports itself with Region mask 0x00400000. Regions: 1 2 3 4 5 6 8

libdvdread: Attempting to retrieve all CSS keys
libdvdread: This can take a _long_ time, please be patient

libdvdread: Get key for /VIDEO_TS/VIDEO_TS.VOB at 0x00000134
libdvdread: Elapsed time 0
libdvdread: Get key for /VIDEO_TS/VTS_01_0.VOB at 0x000001ab
libdvdread: Elapsed time 0
libdvdread: Get key for /VIDEO_TS/VTS_01_1.VOB at 0x00000c7e
libdvdread: Elapsed time 0
libdvdread: Get key for /VIDEO_TS/VTS_02_0.VOB at 0x001034fd
libdvdread: Elapsed time 0
libdvdread: Get key for /VIDEO_TS/VTS_02_1.VOB at 0x0010354a
libdvdread: Elapsed time 0
libdvdread: Found 2 VTS's
libdvdread: Elapsed time 0
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libdvdnav: Language 'en' not found, using 'nl' instead
libdvdnav: Menu Languages available: nl 
libva info: VA-API version 1.1.0
libva info: va_getDriverName() returns 0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/i965_drv_video.so
libva info: Found init function __vaDriverInit_1_1
libva info: va_openDriver() returns 0
[00007f2c9c06d5f0] vaapi generic error: config doesn't support forced fourcc
Failed to open VDPAU backend libvdpau_i965.so: kan gedeeld objectbestand niet openen: Bestand of map bestaat niet
[00007f2c9804a370] main decoder error: buffer deadlock prevented
Drijvendekomma-berekeningsfout (geheugendump gemaakt)
katrien@katrien-ThinkPad-T400:~$ ^C
katrien@katrien-ThinkPad-T400:~$ ^C
katrien@katrien-ThinkPad-T400:~$ 

katrien@katrien-ThinkPad-T400:~$ dpkg -l | grep vdpau
ii  libvdpau1:amd64                            1.1.1-3ubuntu1                               amd64        Video Decode and Presentation API for Unix (libraries)
ii  mesa-vdpau-drivers:amd64                   19.0.2-1ubuntu1.1~18.04.2                    amd64        Mesa VDPAU video acceleration drivers
ii  vdpau-driver-all:amd64                     1.1.1-3ubuntu1                               amd64        Video Decode and Presentation API for Unix (driver metapackage)
ii  vdpau-va-driver:amd64                      0.7.4-6ubuntu1                               amd64        VDPAU-based backend for VA API
katrien@katrien-ThinkPad-T400:~$ ^C
katrien@katrien-ThinkPad-T400:~$