Problem with MPlayer

I posted it to MPlayer list, but no reply....so here it goes...and o yes....I have RTFM'd. I have a vob that I have extracted from a DVD. when I run mplayer like follows: mplayer ROMEO_MUST_DIE20-1.vob -ss 20 I notice that mplayer does not start at 20 seconds into the vob. I start with the above command and immediately pause the player. I see the following tarting playback... A: 34.3 V: 34.3 A-V: 0.058 ct: 0.160 20/ 20 17% 10% 1.1% 0 0 0% Notice that mplayer starts at 34.3 secs instead of 20 secs. What I am doing wrong? How can I start mplayer at 34.3, which is hte # that is displayed when I am playing my vob? Salman