Hello,

You have to edit the file main.js file:

$('.codeless_slider').imagesLoaded(function(){
		$loading.css('display', 'none');
		var c_speed = $('.codeless_slider').data('speed');
		if(c_speed == 'undefined')
			c_speed = 800;
		codelessSlider = new Swiper('.codeless_slider',{ 
			slidesPerView: slide_per_view,
			paginationAsRange: false,
			loop: false,
			touchRatio: 0.7,
			autoplay: 5000,
			speed: c_speed,
			noSwiping: true,

Now you have to change the c_speed value from 800 in 1600.
and also you have to change:

$('.codeless_slider').imagesLoaded(function(){
		$loading.css('display', 'none');
		var c_speed = $('.codeless_slider').data('speed');
		if(c_speed == 'undefined')
			c_speed = 1600;
		codelessSlider = new Swiper('.codeless_slider',{ 
			slidesPerView: slide_per_view,
			paginationAsRange: false,
			loop: false,
			touchRatio: 0.7,
			autoplay:{
                            delay:5000,
                            reverseDirection:false,
                         },
			speed: c_speed,
			noSwiping: true,

Save the file and let us know.

Regards!