Hi Arthur,
Thanks for your question. This support site is specifically for BoldGrid products such as Crio Pro WordPress theme and BoldGrid Post and Page Builder for WordPress.
I’m not too familiar with the Master Slider Plugin and I see you’re using the TwentyThirteen WordPress theme. My suggestion here is to make sure that your theme and all plugins are up to date and there are no relevant errors in the console.
You should try reaching out to the plugin developer directly. I found a support forum for them on wordpress.org.
You should be able to get further assistance there. I hope this helps!