Audio plays but video does not jw player

We have designed a tool using PHP and embedded JW player in it. All the videos which we play are in MP4 format. However some videos play and the others don't. All we can hear is the audio but the video never loads. On investigating we found if the video data rate is equal to or below 1200 kbps then the video plays but if above 1200 kbps then this problem occurs. We converted the videos above 1200 kbps using format factory converter (frames per second = original frame rate; data rate = 1024 kbps; encoding = AVC H.264) and the video now plays. However due to conversion,there is a slight shift (100 to 200 milliseconds) in the frames of the converted video as compared to the original. We would actually want to eliminate the conversion process and would want to play the videos as it is. How do we do it? Else please suggest a converter that wouldn't shift the frames.Please guide.

Thanks,
Jaydeep

Hello,

It sound like a transcdoing issue, try to use this very good software for encoding, it's handbrake.fr :

www.handbrake.fr/

set the preset to "Ipad" and check the "web optimized" radio button.

Thanks,

Will check & revert with the results.