[vdr] mplayer and mpeg4 ?!

[Otto =?iso-8859-15?q?Brandst=E4tter?= <office@brandstaetter.org>]

Good afternoon list !

I have the following problem:
when using mplayer with vdr everything is fine, except when I try to play 
mpeg4 files I created from vdr-files using mencoder.
I hear the sound, but my tv screen stays black.
It _seems_ as I could also seek within the files, but there is no picture.
I do not get error messages in console nor in /var/log/messages
I am using mplayer 0.90pre6-2.96, but I also tried the cvs version.
Also installed divx4linux501.

Did anyone have similar problems ? Any hints ?

Thanks a lot !

Otto