video seek over rtsp problem

I’m playing vod video served by Wowza with rtsp. If I play the stream without seek there is no problem.

After playing wideo longer than 2000 seconds,

If I request setting the position with gst_element_seek_simple (…) to let say 20 seconds, the reported position is set far a way like 1800 secs. Sometimes wowza server sets the position to 20 secs ± offset, then starts to play again 1800 secs.

If I do same seeking process when video has not been played longer than 300 secs there is no problem.

Note: when I play the video with same player from video file there is no problem at all.