Some post images can not be shown

[guangzhen]

Please refer my website:

Especially in my iPhone, when I scroll up, the image of replies from 1-5 can not be shown sometimes, around 80% times.
I had a short analyze about this, found the hidden image tag data-state always stays 'loading'.
In my laptop, around 20% times it will not be shown.
Is is caused by network condition? or it's a bug in image.js?