gmplayer:mplayer:xine - cpu drain!?

[ChojinDSL]

My system is a PIII 450mhz with 768 mb ram and a Geforce4mx.

With Gmplayer, when I play a mpg file, I get 70-80% cpu drain.
If I use the commandline mplayer , I only get 14-20% cpu drain.
Also if I use xine , I only get 14-20% cpu drain.
With Gxine, I get also about 14-20% cpu drain.
The file I am playing is a standard Mpeg1 file at 320x240 resolution.

Is it normal that Gmplayer needs so much more cpu power than mplayer or xine?
Or is something wrong with my config?

Has anyone else experienced something like this?