effect="random" doesn't work (gallery)

Hi,
I wanted to randomize my photo gallery and I found somewhere, that I needed to add to my code this line -> effect=”random”. Unfortunately it doesn’t work. The order I have is by ID numbers. It doesn’t change even when I change the order manually in my shortcode.

Thank you for your help.

I’m on wp4.0 and su4.9.2

here’s my code:
[su_custom_gallery source="media: 1353,1354,1355,1356,1357,1358,1359,1360,1361" limit="20" link="custom" target="blank" width="106" height="106" effect="random"]

https://wordpress.org/plugins/shortcodes-ultimate/