We have a camera that uploads avi files to our wowza servers on motion detection. We then run ffmpeg to convert the file to mp4 and we use libx264 for encoding.

Then, we use the standard wowza vod application to stream this video to ios devices.

The video plays just fine on devices with ios 6 or lower but it freezes on the first frame for ios 6.1 and ios 7. The file plays fine on all ios versions (including 6.1 and 7) if we transfer the file to the device and play it locally.
However when we stream it from wowza vod app. it does not play on ios 6.1 and up as stated previously.

We have tried fully decoding the video to yuv format and re-encoding it with ffmpeg but still the video hangs on the first frame on ios 6.1+

Anybody have any idea, what could be wrong with the file? Any pointers for debugging greatly appreciated.