I'm currently having issues with a dynamically loaded html video player on my site, where I set the source of a HTML video player using JS by clicking on a button.

The problem is, once the video is playing it runs fine, but as soon as I skim the video or jump ahead, doesn't matter how far, the sound is lost and doesn't sync back up with the video, even though I'm on a fast connection and the video itself continues to play without any hiccups or buffering.

The video is a MP4 encoded in H.264 and ACC 160bit.

What could this be due to?

EDIT: this problem only seems to occur on iOS devices, and on any browser.