I experience tearing in videos using the xv output and also in flash videos but everything is fine using the gl output with mplayer. Many iptv players don't allow the user to use any other video output than xv.
My system relies on an i2500k with an asus P8H67-M Pro (rev B3). I installed a kubuntu 11.04 (64-bit version). My screen consists in a sony tv connected to the hdmi output.
2.6.38-8-generic #42-Ubuntu SMP Mon Apr 11 03:31:24 UTC 2011 x86_64 x86_64
The desktop effects of KDE are disabled otherwise plasma crashes at the end
of any video playback in mplayer.
The content of the file ~/.kde/share/config/kwinrc is as follow: