Video clips in instagram uploaded as carousel are starting with black fade in before playing

Hello everyone,

I wondered if anyone had any ideas what was going on here?

I am uploading multiple clips to instagram in one post. The idea is to have the posts swipe from left to right seamlessly. For some reason instagram is adding a fade in from black on multiple slides so it looks kind of jittery. I have checked the clips and they don't have the fade, I have also tried to select a cover manually for each of the clips in the post. No luck there.

I wondered if anyone had experienced this before and had a solution, or if anyone had any idea what was going wrong?

Perhaps its an export/file issue. Maybe connectivity? I have tried multiple devices and different accounts.

Here is a clip of what is happening,
https://www.dropbox.com/s/ex74lvvvdedwjda/Screen_Recording_20211222-095737_Instagram.mp4?dl=0

Anyway advice would be greatly appreciated.

Cheers

Alex