WordPress Build in Slideshow goes way to fast

Ok so a while ago a friend of mine picked up a job to build a website. Unfortunatly he was working full time and starting college so he wasn’t able to finish. I took over the project and got everything up and runnning. However before he stopped working on the project he added some sort of slideshow to one of the pages. And I can’t figure out what he used or how he did it. There are no plugins that affect the slideshow, and not even any shortcode on the page the slideshow is on. Which was fine at first because the slideshow was what the client wanted. The images are stored under the “Media” thing in WP and are assigned to that page.
Now heres the problem: when I changed from a free theme to a theme the client bought the slideshow sped up. it now goes really fast and from what i can tell in the HTML code it changes the image every second. now how do I edit this and slow it down?

the website and page is:
https://greenenergyconceptsstore.org/recent-projects/
here is the code

[code]
<div class="slideshow-holder"></div><script type="text/javascript">/* <![CDATA[ */ psTimeout[0]=12;psTrans[0]='fade';psNoWrap[0]=0;psSpeed[0]=1;/* ]]> */</script><div id="slideshow-wrapper0" class="slideshow-wrapper">
<div class="slideshow-nav0 slideshow-nav">PausePlayPrev<span class="sep">|</span>Next<span class="slideshow-info0 slideshow-info"></span></div>

<div id="portfolio-slideshow0" class="portfolio-slideshow">
<div class="fade slideshow-next slideshow-content">
<img width="2592" height="1944" src="https://greenenergyconceptsstore.org/wp-content/uploads/2011/08/2011-03-24-12.23.292.jpg" class="attachment-full" alt="2011-03-24-12.23.29" title="2011-03-24-12.23.29" /><p class="slideshow-title">2011-03-24-12.23.29</p></div>
<div class="not-first fade slideshow-next slideshow-content">
<img width="2592" height="1944" src="https://greenenergyconceptsstore.org/wp-content/uploads/2011/08/2011-03-31-15.00.132.jpg" class="attachment-full" alt="2011-03-31-15.00.13" title="2011-03-31-15.00.13" /><p class="slideshow-title">2011-03-31-15.00.13</p></div>
<div class="not-first fade slideshow-next slideshow-content">
<img width="2592" height="1944" src="https://greenenergyconceptsstore.org/wp-content/uploads/2011/08/2011-04-08-16.49.492.jpg" class="attachment-full" alt="2011-04-08-16.49.49" title="2011-04-08-16.49.49" /><p class="slideshow-title">2011-04-08-16.49.49</p></div>

<div class="not-first fade slideshow-next slideshow-content">
<img src="https://greenenergyconceptsstore.org/wp-content/uploads/2011/08/september-2010-super-8-0182.jpg" class="attachment-full" alt="september-2010-super-8-018" title="september-2010-super-8-018" /><p class="slideshow-title">september-2010-super-8-018</p></div>
</div><!--#portfolio-slideshow--></div><!--#slideshow-wrapper-->
[/code]

help would be appreciated thanks.