@branja - are you sure you did not forget to execute:
apt-get remove gstreamer0.10-openmax after installing HD codecs?

@Estel - dmesg does not need root account

@Megaltariak - yeah, I know about the problem, seems like gstdsp does not clean up correctly or whatever, still this is a bug in gst-dsp, I've tried to fix it several times, yet no success . Maybe I should try to get help from Felipe Contreras (gst-dsp author).

BTW a simple "killall mafw-dbus-wrapper" does do job and videos start to play from the first try again.

@rslick - you should execute the command in the same directory you've downloaded the .debs.

"Nokia N900" is actually "/home/user/MyDocs"