This site is using Propulsion 2.0 and after upgrading to 3.7.1 after rotating 2 slides, no others will show and the forward/back controls will not operate on Featured Media Slideshow
Fader Slider, Auto Rotate=yes, size – adjustable slider.
I deactivated plugins (not using many) but it didn’t help so I turned them back on.
Please try updating the theme once again. You should login on ThemeForest with the account you have purchased Propulsion theme and go to Downloads section to download it. Please update via FTP
For a quick guide on updating your theme take a look at this video on updating the theme via FTP: https://vimeo.com/channels/aviathemes/67209750