Homepage slider not display all post in responsive layout

On my homepage I am using the Big slide set with a max of 4 posts and the page is set to have unique articles. When I view the homepage on my iPhone, it only displays the first post in the slider, and not the other 3 posts. If unique articles is enabled and the Big slide is set to latest, the other 3 posts are never visible. Only the very first post.

All 4 posts can be seen: http://awesomescreenshot.com/0272hvl7ef
Only first post can be seen: http://awesomescreenshot.com/0362hvla7a

The other 3 posts in the Big slide disappear.

Is there any way around this other than to disable the unique articles feature?

hi,
when you view the site on you iPhone the them rearrange itself.
the slider changes, it will display one image, but you can use your finger to slide it to right or left, and you will see all the other images.

Thanks for you message.
Radu A.

Okay so I changed the slider from showing only 4 posts to 8 posts. And while yes I can slide left or right, it still does not show the other 3 posts in each slide group. It still only shows the very first post of each slide group.

Here is a video I made showing the problem. In the video when I slide, you are only seeing the first post of each slide group. I have the slide set to display 8 posts. Yet I am only able to slide through 2 posts.